Pseudo-block copolymers and process employing chain shuttling agent

ABSTRACT

A process for the polymerization of one or more addition polymerizable monomers to form a copolymer comprising multiple regions or segments of differentiated polymer composition or properties comprising contacting an addition polymerizable monomer or mixture of monomers under addition polymerization conditions with a composition comprising at least one olefin polymerization catalyst, a cocatalyst and a chain shuttling agent, said process being characterized by formation of at least some of the growing polymer chains under differentiated process conditions such that two or more blocks or segments formed within at least some of the resulting polymer are chemically or physically distinguishable.

CROSS REFERENCE STATEMENT

This application claims the benefit of U.S. Provisional Application No.60/662,938, filed Mar. 17, 2005.

BACKGROUND OF THE INVENTION

The present invention relates to a process for polymerizing a monomer ormixtures of two or more monomers such as mixtures of ethylene and one ormore comonomers, to form an interpolymer product having unique physicalproperties, to a process for preparing such interpolymers, and to theresulting polymer products. In another aspect, the invention relates tothe articles prepared from these polymers. The inventive polymerscomprise two or more differing regions or segments (blocks) causing thepolymer to possess unique physical properties. These pseudo-blockcopolymers and polymeric blends comprising the same are usefullyemployed in the preparation of solid articles such as moldings, films,sheets, and foamed objects by molding, extruding, or other processes,and are useful as components or ingredients in adhesives, laminates,polymeric blends, and other end uses. The resulting products are used inthe manufacture of components for automobiles, such as profiles, bumpersand trim parts; packaging materials; electric cable insulation, andother applications.

It has long been known that polymers containing a block-type structureoften have superior properties compared to random copolymers and blends.For example, triblock copolymers of styrene and butadiene (SBS) andhydrogenated versions of the same (SEBS) have an excellent combinationof heat resistance and elasticity. Other block copolymers are also knownin the art. Generally, block copolymers known as thermoplasticelastomers (TPE) have desirable properties due to the presence of “soft”or elastomeric block segments connecting “hard” either crystallizable orglassy blocks in the same polymer. At temperatures up to the melttemperature or glass transition temperature of the hard segments, thepolymers demonstrate elastomeric character. At higher temperatures, thepolymers become flowable, exhibiting thermoplastic behavior. Knownmethods of preparing block copolymers include anionic polymerization andcontrolled free radical polymerization. Unfortunately, these methods ofpreparing block copolymers require sequential monomer addition and batchprocessing and the types of monomers that can be usefully employed insuch methods are relatively limited. For example, in the anionicpolymerization of styrene and butadiene to form a SBS type blockcopolymer, each polymer chain requires a stoichiometric amount ofinitiator and the resulting polymers have extremely narrow molecularweight distribution, Mw/Mn, preferably from 1.0 to 1.3. Additionally,anionic and free-radical processes are relatively slow, resulting inpoor process economics.

It would be desirable to produce block copolymers catalytically, thatis, in a process wherein more than one polymer molecule is produced foreach catalyst or initiator molecule. In addition, it would be highlydesirable to produce copolymers having properties resembling blockcopolymers from olefin monomers such as ethylene, propylene, and higheralpha-olefins that are generally unsuited for use in anionic orfree-radical polymerizations. In certain of these polymers, it is highlydesirable that some or all of the polymer blocks comprise amorphouspolymers such as a copolymer of ethylene and a comonomer, especiallyamorphous random copolymers comprising ethylene and an α-olefin having3, and especially 4, or more carbon atoms.

Previous researchers have stated that certain homogeneous coordinationpolymerization catalysts can be used to prepare polymers having asubstantially “block-like” structure by suppressing chain-transferduring the polymerization, for example, by conducting the polymerizationprocess in the absence of a chain transfer agent and at a sufficientlylow temperature such that chain transfer by β-hydride elimination orother chain transfer processes is essentially eliminated. Under suchconditions, the sequential addition of different monomers was said toresult in formation of polymers having sequences or segments ofdifferent monomer content. Several examples of such catalystcompositions and processes are reviewed by Coates, Hustad, and Reinartzin Angew. Chem., Int. Ed., 41, 2236-2257 (2002) as well asUS-A-2003/0114623.

Disadvantageously, such processes require sequential monomer additionand result in the production of only one polymer chain per activecatalyst center, which limits catalyst productivity. In addition, therequirement of relatively low process temperatures increases the processoperating costs, making such processes unsuited for commercialimplementation. Moreover, the catalyst cannot be optimized for formationof each respective polymer type, and therefore the entire processresults in production of polymer blocks or segments of less than maximalefficiency and/or quality. For example, formation of a certain quantityof prematurely terminated polymer is generally unavoidable, resulting inthe forming of blends having inferior polymer properties. Accordingly,under normal operating conditions, for sequentially prepared blockcopolymers having Mw/Mn of 1.5 or greater, the resulting distribution ofblock lengths is relatively inhomogeneous, not a most probabledistribution.

For these reasons, it would be highly desirable to provide a process forproducing olefin copolymers comprising at least some quantity of blocksor segments having differing physical properties in a process usingcoordination polymerization catalysts capable of operation at highcatalytic efficiencies. In addition, it would be desirable to provide aprocess and resulting copolymers wherein insertion of terminal blocks orsequencing of blocks within the polymer can be influenced by appropriateselection of process conditions. Finally, if would be highly desirableto be able to use a continuous process for production of blockcopolymers.

The use of certain metal alkyl compounds and other compounds, such ashydrogen, as chain transfer agents to interrupt chain growth in olefinpolymerizations is well known in the art. In addition, it is known toemploy such compounds, especially aluminum alkyl compounds, asscavengers or as cocatalysts in olefin polymerizations. InMacromolecules, 33, 9192-9199 (2000) the use of certain aluminumtrialkyl compounds as chain transfer agents in combination with certainpaired zirconocene catalyst compositions resulted in polypropylenemixtures containing small quantities of polymer fractions containingboth isotactic and atactic chain segments. In Liu and Rytter,Macromolecular Rapid Comm., 22, 952-956 (2001) and Bruaseth and Rytter,Macromolecules, 36, 3026-3034 (2003) mixtures of ethylene and 1-hexenewere polymerized by a similar catalyst composition containingtrimethylaluminum chain transfer agent. In the latter reference, theauthors summarized the prior art studies in the following manner (somecitations omitted):

-   -   “Mixing of two metallocenes with known polymerization behavior        can be used to control polymer microstructure. Several studies        have been performed of ethene polymerization by mixing two        metallocenes. Common observations were that, by combining        catalysts which separately give polyethene with different Mw,        polyethene with broader and in some cases bimodal MWD can be        obtained. [S]oares and Kim (J. Polym. Sci., Part A: Polym.        Chem., 38, 1408-1432 (2000)) developed a criterion in order to        test the MWD bimodality of polymers made by dual single-site        catalysts, as exemplified by ethene/1-hexene copolymerization of        the mixtures Et(Ind)₂ZrCl₂/Cp₂HfCl₂ and Et(Ind)₂ZrCl₂/CGC        (constrained geometry catalyst) supported on silica. Heiland and        Kaminsky (Makromol. Chem., 193, 601-610 (1992)) studied a        mixture of Et-(Ind)₂ZrCl₂ and the hafnium analogue in        copolymerization of ethene and 1-butene.    -   These studies do not contain any indication of interaction        between the two different sites, for example, by readsorption of        a terminated chain at the alternative site. Such reports have        been issued, however, for polymerization of propene. Chien et        al. (J. Polym. Sci. Part A: Polym. Chem., 37, 2439-2445 (1999),        Makromol., 30, 3447-3458 (1997)) studied propene polymerization        by homogeneous binary zirconocene catalysts. A blend of        isotactic polypropylene (i-PP), atactic polypropylene (a-PP),        and a stereoblock fraction (i-PP-b-a-PP) was obtained with a        binary system comprising an isospecific and an aspecific        precursor with a borate and TIBA as cocatalyst. By using a        binary mixture of isospecific and syndiospecific zirconocenes, a        blend of isotactic polypropylene (i-PP), syndiotactic        polypropylene (s-PP), and a stereoblock fraction (i-PP-b-s-PP)        was obtained. The mechanism for formation of the stereoblock        fraction was proposed to involve the exchange of propagating        chains between the two different catalytic sites. Przybyla and        Fink (Acta Polym., 50, 77-83 (1999)) used two different types of        metallocenes (isospecific and syndiospecific) supported on the        same silica for propene polymerization. They reported that, with        a certain type of silica support, chain transfer between the        active species in the catalyst system occurred, and stereoblock        PP was obtained. Lieber and Brintzinger (Macromol. 3, 9192-9199        (2000)) have proposed a more detailed explanation of how the        transfer of a growing polymer chain from one type of metallocene        to another occurs. They studied propene polymerization by        catalyst mixtures of two different ansa-zirconocenes. The        different catalysts were first studied individually with regard        to their tendency toward alkyl-polymeryl exchange with the        allylaluminum activator and then pairwise with respect to their        capability to produce polymers with a stereoblock structure.        They reported that formation of stereoblock polymers by a        mixture of zirconocene catalysts with different        stereoselectivities is contingent upon an efficient polymeryl        exchange between the Zr catalyst centers and the Al centers of        the cocatalyst.”

Brusath and Rytter then disclosed their own observations using pairedzirconocene catalysts to polymerize mixtures of ethylene/1-hexene andreported the effects of the influence of the dual site catalyst onpolymerization activity, incorporation of comonomer, and polymermicrostructure using methylalumoxane cocatalyst.

Analysis of the foregoing results indicate that Rytter and coworkerslikely failed to utilize combinations of catalyst, cocatalyst, and thirdcomponents that were capable of readsorption of the polymer chain fromthe chain transfer agent onto both of the active catalytic sites, thatis, two-way readsorption. While indicating that chain termination due tothe presence of trimethylaluminum likely occurred with respect topolymer formed from the catalyst incorporating minimal comonomer, andthereafter that polymeryl exchange with the more open catalytic sitefollowed by continued polymerization likely occurred, evidence of thereverse flow of polymer ligands appeared to be lacking in the reference.In fact, in a later communication, Rytter, et. al., Polymer, 45,7853-7861 (2004), it was reported that no chain transfer between thecatalyst sites actually took place in the earlier experiments. Similarpolymerizations were reported in WO98/34970.

In U.S. Pat. Nos. 6,380,341 and 6,169,151, use of a “fluxional”metallocene catalyst, that is a metallocene capable of relatively facileconversion between two stereoisomeric forms having differingpolymerization characteristics such as differing reactivity ratios wassaid to result in production of olefin copolymers having a “blocky”structure. Disadvantageously, the respective stereoisomers of suchmetallocenes generally fail to possess significant difference in polymerformation properties and are incapable of forming both highlycrystalline and amorphous block copolymer segments, for example, from agiven monomer mixture under fixed reaction conditions. Moreover, becausethe relative ratio of the two “fluxional” forms of the catalyst cannotbe varied, there is no ability, using “fluxional” catalysts, to varypolymer block composition or the ratio of the respective blocks. Forcertain applications, it is desirable to produce polymers havingterminal blocks that are highly crystalline, functionalized or morereadily functionalized, or that possess other distinguishing properties.For example, it is believed that polymers wherein the terminal segmentsor blocks are crystalline or glassy possess improved abrasionresistance. In addition, polymers wherein the blocks having amorphousproperties are internal or primarily connected between crystalline orglassy blocks, have improved elastomeric properties, such as improvedretractive force and recovery, particularly at elevated temperatures.

In JACS, 2004, 126, 10701-10712, Gibson, et al discuss the effects of“catalyzed living polymerization” on molecular weight distribution. Theauthors define catalyzed living polymerization in this manner:

-   -   “ . . . if chain transfer to aluminum constitutes the sole        transfer mechanism and the exchange of the growing polymer chain        between the transition metal and the aluminum centers is very        fast and reversible, the polymer chains will appear to be        growing on the aluminum centers. This can then reasonably be        described as a catalyzed chain growth reaction on aluminum . . .        . An attractive manifestation of this type of chain growth        reaction is a Poisson distribution of product molecular weights,        as opposed to the Schulz-Flory distribution that arises when β-H        transfer accompanies propagation.”

The authors reported the results for the catalyzed livinghomopolymerization of ethylene using an iron containing catalyst incombination with ZnEt₂, ZnMe₂, or Zn(i-Pr)₂. Homoleptic alkyls ofaluminum, boron, tin, lithium, magnesium and lead did not inducecatalyzed chain growth. Using GaMe₃ as cocatalyst resulted in productionof a polymer having a narrow molecular weight distribution. However,after analysis of time-dependent product distribution, the authorsconcluded this reaction was, “not a simple catalyzed chain growthreaction.” Accordingly, the product would not have constituted apseudo-block copolymer. Similar processes employing single catalystshave been described in U.S. Pat. Nos. 5,210,338, 5, 276,220, and6,444,867.

Earlier workers had made similar claims to forming block copolymersusing a single Ziegler-Natta type catalyst in multiple reactors arrangedin series. Examples of such teachings include U.S. Pat. Nos. 3,970,719and 4,039,632. It is now known that no substantial block copolymerformation takes place under these reaction conditions.

In U.S. Pat. Nos. 6,319,989 and 6,683,149, the use of two loop reactorsconnected in series and operating under differing polymerizationconditions to prepare either broad or narrow molecular weight polymerproducts was disclosed. The references fail to disclose the use of chaintransfer agents and the formation of pseudo-block copolymer products.

Accordingly, there remains a need in the art for a polymerizationprocess that is capable of preparing copolymers having propertiesapproximating those of linear multi-block copolymers, in a high yieldprocess adapted for commercial utilization. Moreover, it would bedesirable if there were provided an improved process for preparingpolymers, especially copolymers of two or more comonomers such asethylene and one or more comonomers, by the use of a shuttling agent tointroduce block-like properties in the resulting polymer (pseudo-blockcopolymers). In addition it would be desirable to provide such animproved process that is capable of preparing copolymers having arelatively narrow molecular weight distribution and non-randomdistribution of polymer segments or regions. Finally, it would bedesirable to provide an improved process for preparing the foregoingdesirable pseudo-block copolymer products in a continuous process.

SUMMARY OF THE INVENTION

According to the present invention there are now provided a process forthe polymerization of one or more addition polymerizable monomers,preferably of two or more addition polymerizable monomers, especiallyethylene and at least one copolymerizable comonomer, propylene and atleast one copolymerizable comonomer, or 4-methyl-1-pentene and at leastone copolymerizable comonomer, to form a copolymer comprising multipleregions of differentiated polymer composition or properties, especiallyregions comprising differing comonomer incorporation, said processcomprising contacting an addition polymerizable monomer or mixture ofmonomers under addition polymerization conditions with a compositioncomprising at least one olefin polymerization catalyst, a cocatalyst anda chain shuttling agent, said process being characterized by formationof at least some of the growing polymer chains under differentiatedprocess conditions such that two or more blocks or segments formedwithin at least some of the resulting polymer are chemically orphysically distinguishable.

In another embodiment of the invention there is provided a copolymer,especially such a copolymer comprising in polymerized form ethylene anda copolymerizable comonomer, propylene and at least one copolymerizablecomonomer, or 4-methyl-1-pentene and at least one copolymerizablecomonomer, said copolymer comprising two or more intramolecular regionscomprising differing chemical or physical properties, especially regionsof differentiated comonomer incorporation. Highly preferably thecopolymer possesses a molecular weight distribution, Mw/Mn, of less than3.0, preferably less than 2.8.

In a still further embodiment of the present invention, there isprovided a polymer mixture comprising: (1) an organic or inorganicpolymer, preferably a homopolymer of ethylene or of propylene and/or acopolymer of ethylene or propylene and a copolymerizable comonomer, and(2) a pseudo-block copolymer according to the present invention orprepared according to the process of the present invention. In adesirable embodiment component (1) is a matrix polymer comprising highdensity polyethylene or isotactic polypropylene and component (2) is anelastomeric pseudo-block copolymer. In a preferred embodiment, component(2) comprises occlusions of the matrix polymer formed during compoundingof components (1) and (2).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of the process of copolymerformation according to the present invention.

FIG. 2 is a schematic representation of a continuous loop reactorsuitable for use in the present invention.

DETAILED DESCRIPTION OF THE INVENTION

All references to the Periodic Table of the Elements herein shall referto the Periodic Table of the Elements, published and copyrighted by CRCPress, Inc., 2003. Also, any references to a Group or Groups shall be tothe Group or Groups reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups. Unless stated to thecontrary, implicit from the context, or customary in the art, all partsand percents are based on weight. For purposes of United States patentpractice, the contents of any patent, patent application, or publicationreferenced herein are hereby incorporated by reference in their entirety(or the equivalent US version thereof is so incorporated by reference)especially with respect to the disclosure of synthetic techniques,definitions (to the extent not inconsistent with any definitionsprovided herein) and general knowledge in the art.

The term “comprising” and derivatives thereof is not intended to excludethe presence of any additional portion, component, step or procedure,whether or not the same is disclosed herein. In order to avoid anydoubt, all compositions claimed herein through use of the term“comprising” may include any additional additive, adjuvant, or compoundwhether polymeric or otherwise, unless stated to the contrary. Incontrast, the term, “consisting essentially of” excludes from the scopeof any succeeding recitation any other portion, component, step orprocedure, excepting those that are not essential to operability. Theterm “consisting of” excludes any portion, component, step or procedurenot specifically delineated or listed. The term “or”, unless statedotherwise, refers to the listed members individually as well as in anycombination.

The term “polymer”, includes both homopolymers, that is, homogeneouspolymers prepared from a single monomer, and copolymers (interchangeablyreferred to herein as interpolymers), meaning polymers prepared byreaction of at least two monomers or otherwise containing chemicallydifferentiated segments or blocks therein even if formed from a singlemonomer. More specifically, the term “polyethylene” includeshomopolymers of ethylene and copolymers of ethylene and one or more C₃₋₈α-olefins. The term “crystalline” if employed, refers to a polymer thatpossesses a first order transition or crystalline melting point (Tm) asdetermined by differential scanning calorimetry (DSC) or equivalenttechnique. The term may be used interchangeably with the term“semicrystalline”. The term “amorphous” refers to a polymer lacking acrystalline melting point.

The term “pseudo-block copolymer” refers to a copolymer comprising twoor more regions or segments (referred to as “blocks”) of differingchemical or physical property, such as variable comonomer content,crystallinity, density, tacticity, regio-error, or other property,preferably joined in a linear manner, that is, a polymer comprisingblocks which are joined end-to-end, rather than in pendent or graftedfashion. The various blocks are not necessarily of identical chemicalcomposition, but vary, at least somewhat, in one or more of theforegoing respects, from the composition of adjacent blocks or regions.Compared to random copolymers, the polymers of the invention possesssufficient differences in chemical properties, especially crystallinity,between blocks or segments, to achieve many of the desired properties oftrue block copolymers, such as thermoplastic elastomeric properties,while at the same time being amenable to preparation in conventionalolefin polymerization processes, especially continuous solutionpolymerization processes employing catalytic quantities ofpolymerization catalysts. Compared to block copolymers of the prior art,including copolymers produced by sequential monomer addition, fluxionalcatalysts, or anionic polymerization techniques, the copolymers of theinvention are characterized by unique distributions of polymerpolydispersity (PDI or Mw/Mn), block length distribution, and, mostsignificantly, block composition distribution. This is due, in apreferred embodiment, to the effect of the use of a shuttling agent(s)in combination with a high activity metal complex based polymerizationcatalyst in a polymerization process having multiple polymerizationzones or continuous variation in one or more polymerization conditions.More specifically, the polymers desirably possess PDI from 1.7 to 2.9,preferably from 1.8 to 2.5.

In addition, the pseudo-block copolymers of the invention desirablypossess a PDI fitting a Schutz-Flory distribution rather than a Poissondistribution. The use of the present polymerization process results in aproduct having a polydisperse block distribution, a polydispersedistribution of block sizes, and/or a polydisperse block compositiondistribution. This ultimates in the formation of polymer products havingimproved and distinguishable physical properties. The theoreticalbenefits of a polydisperse block distribution have been previouslymodeled and discussed in Potemkin, Physical Review E (1998) 57(6), p.6902-6912, and Dobrynin, J. Chem. Phys. (1997) 107(21), p 9234-9238.

As used herein with respect to a chemical compound, unless specificallyindicated otherwise, the singular includes all isomeric forms and viceversa (for example, “hexane”, includes all isomers of hexaneindividually or collectively). The terms “compound” and “complex” areused interchangeably herein to refer to organic-, inorganic- andorganometal compounds. The term, “atom” refers to the smallestconstituent of an element regardless of ionic state, that is, whether ornot the same bears a charge or partial charge or is bonded to anotheratom. The term “heteroatom” refers to an atom other than carbon orhydrogen. Preferred heteroatoms include: F, Cl, Br, N, O, P, B, S, Si,Sb, Al, Sn, As, Se and Ge.

The term, “hydrocarbyl” refers to univalent substituents containing onlyhydrogen and carbon atoms, including branched or unbranched, saturatedor unsaturated, cyclic or noncyclic species. Examples include alkyl-,cycloalkyl-, alkenyl-, alkadienyl-, cycloalkenyl-, cycloalkadienyl-,aryl-, and alkynyl-groups. “Substituted hydrocarbyl” refers to ahydrocarbyl group that is substituted with one or more nonhydrocarbylsubstituent groups. The terms, “heteroatom containing hydrocarbyl” or“heterohydrocarbyl” refer to univalent groups in which at least one atomother than hydrogen or carbon is present along with one or more carbonatom and one or more hydrogen atoms. The term “heterocarbyl” refers togroups containing one or more carbon atoms and one or more heteroatomsand no hydrogen atoms. The bond between the carbon atom and anyheteroatom as well as the bonds between any two heteroatoms, may besaturated or unsaturated. Thus, an alkyl group substituted with aheterocycloalkyl-, substituted heterocycloalkyl-, heteroaryl-,substituted heteroaryl-, alkoxy-, aryloxy-, dihydrocarbylboryl-,dihydrocarbylphosphino-, dihydrocarbylamino-, trihydrocarbylsilyl-,hydrocarbylthio-, or hydrocarbylseleno-group is within the scope of theterm heteroalkyl. Examples of suitable heteroalkyl groups includecyano-, benzoyl-, (2-pyridyl)methyl-, and trifluoromethyl-groups.

As used herein the term “aromatic” refers to a polyatomic, cyclic,conjugated ring system containing (4δ+2) π-electrons, wherein δ is aninteger greater than or equal to 1. The term “fused” as used herein withrespect to a ring system containing two or more polyatomic, cyclic ringsmeans that with respect to at least two rings thereof, at least one pairof adjacent atoms is included in both rings. The term “aryl” refers to amonovalent aromatic substituent which may be a single aromatic ring ormultiple aromatic rings which are fused together, linked covalently, orlinked to a common group such as a methylene or ethylene moiety. Thearomatic ring(s) may include phenyl, naphthyl, anthracenyl, andbiphenyl, among others.

“Substituted aryl” refers to an aryl group in which one or more hydrogenatoms bound to any carbon is replaced by one or more functional groupssuch as alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl,heterocycloalkyl, substituted heterocycloalkyl, halogen, alkylhalos (forexample, CF₃), hydroxy, amino, phosphido, alkoxy, amino, thio, nitro,and both saturated and unsaturated cyclic hydrocarbons which are fusedto the aromatic ring(s), linked covalently or linked to a common groupsuch as a methylene or ethylene moiety. The common linking group mayalso be a carbonyl as in benzophenone or oxygen as in diphenylether ornitrogen in diphenylamine.

The term, “comonomer incorporation index”, refers to the percentcomonomer incorporated into a copolymer prepared under representativemonomer/comonomer polymerization conditions by the catalyst underconsideration in the absence of other polymerization catalysts, ideallyunder steady-state, continuous solution polymerization conditions atgreater than 95 percent monomer conversion and greater than 0.01 percentcomonomer conversion. The selection of metal complexes or catalystcompositions having the greatest difference in comonomer incorporationindices under the different polymerization conditions results incopolymers from two or more monomers having the largest difference inblock or segment properties, such as density.

In certain circumstances the comonomer incorporation index may bedetermined directly, for example by the use of NMR spectroscopictechniques. Often, however, any difference in comonomer incorporationmust be indirectly determined. For polymers formed from multiplemonomers this may be accomplished by various techniques based on monomerreactivities.

For copolymers produced by a given catalyst, the relative amounts ofcomonomer and monomer in the copolymer and hence the copolymercomposition is determined by relative rates of reaction of comonomer andmonomer. Mathematically the molar ratio of comonomer to monomer is givenby

$\begin{matrix}{\frac{F_{2}}{F_{1}} = {( \frac{\lbrack{comonomer}\rbrack}{\lbrack{monomer}\rbrack} )_{polymer} = \frac{R_{p\; 2}}{R_{p\; 1}}}} & (1)\end{matrix}$

Here R_(p2) and R_(p1) are the rates of polymerization of comonomer andmonomer respectively and F₂ and F₁ are the mole fractions of each in thecopolymer. Because F₁+F₂=1 we can rearrange this equation to

$\begin{matrix}{F_{2} = \frac{R_{p\; 2}}{R_{p\; 1} + R_{p\; 2}}} & (2)\end{matrix}$

The individual rates of polymerization of comonomer and monomer aretypically complex functions of temperature, catalyst, andmonomer/comonomer concentrations. In the limit as comonomerconcentration in the reaction media drops to zero, R_(p2) drops to zero,F₂ becomes zero and the polymer consists of pure monomer. In thelimiting case of no monomer in the reactor R_(p1) becomes zero and F₂ isone (provided the comonomer can polymerize alone).

For most homogeneous catalysts the ratio of comonomer to monomer in thereactor largely determines polymer composition as determined accordingto either the Terminal Copolymerization Model or the PenultimateCopolymerization Model.

For random copolymers in which the identity of the last monomer inserteddictates the rate at which subsequent monomers insert, the terminalcopolymerization model is employed. In this model insertion reactions ofthe type

where C* represents the catalyst, M_(i) represents monomer i, and k_(ij)is the rate constant having the rate equation:R_(p) _(ij) =k_(ij)└ . . . M_(i)C*┘[M_(j)]  (4).

The comonomer mole fraction (i=2) in the reaction media is defined bythe equation:

$\begin{matrix}{f_{2} = {\frac{\lbrack M_{2} \rbrack}{\lbrack M_{1} \rbrack + \lbrack M_{2} \rbrack}.}} & (5)\end{matrix}$

A simplified equation for comonomer composition can be derived asdisclosed in George Odian, Principles of Polymerization, Second Edition,John Wiley and Sons, 1970, as follows:

$\begin{matrix}{F_{2} = {\frac{{r_{1}( {1 - f_{2}} )}^{2} + {( {1 - f_{2}} )f_{2}}}{{r_{1}( {1 - f_{2}} )}^{2} + {2( {1 - f_{2)}} )f_{2}} + {r_{2}f_{2}^{2}}}.}} & (6)\end{matrix}$

From this equation the mole fraction of comonomer in the polymer issolely dependent on the mole fraction of comonomer in the reaction mediaand two temperature dependent reactivity ratios defined in terms of theinsertion rate constants as:

$\begin{matrix}{{r_{1} = \frac{k_{11}}{k_{12}}}{r_{2} = {\frac{k_{22}}{k_{21}}.}}} & (7)\end{matrix}$

Alternatively, in the penultimate copolymerization model, the identitiesof the last two monomers inserted in the growing polymer chain dictatethe rate of subsequent monomer insertion. The polymerization reactionsare of the form:

and the individual rate equations are:R_(p) _(ijk) =K_(ijk)└ . . . M_(i)M_(j)=C*┘[M_(k)]  (9)

The comonomer content can be calculated (again as disclosed in GeorgeOdian, Supra.) as:

$\begin{matrix}{\frac{( {1 - F_{2}} )}{F_{2}} = \frac{1 + \frac{r_{1}^{\prime}{X( {{r_{1}X} + 1} )}}{( {{r_{1}^{\prime}X} + 1} )}}{1 + \frac{r_{2}^{\prime}( {r_{2} + X} )}{X( {r_{2}^{\prime} + X} )}}} & (10)\end{matrix}$

where X is defined as:

$\begin{matrix}{X = \frac{( {1 - f_{2}} )}{f_{2}}} & (11)\end{matrix}$

and the reactivity ratios are defined as:

$\begin{matrix}{{r_{1} = \frac{k_{111}}{k_{112}}}{r_{1}^{\prime} = \frac{k_{211}}{k_{212}}}{r_{2} = \frac{k_{222}}{k_{221}}}{r_{2}^{\prime} = {\frac{k_{122}}{k_{121}}.}}} & (12)\end{matrix}$

For this model as well the polymer composition is a function only oftemperature dependent reactivity ratios and comonomer mole fraction inthe reactor. The same is also true when reverse comonomer or monomerinsertion may occur or in the case of the interpolymerization of morethan two monomers.

Reactivity ratios for use in the foregoing models may be predicted usingwell known theoretical techniques or empirically derived from actualpolymerization data. Suitable theoretical techniques are disclosed, forexample, in B. G. Kyle, Chemical and Process Thermodynamics, ThirdAddition, Prentice-Hall, 1999 and in Redlich-Kwong-Soave (RKS) Equationof State, Chemical Engineering Science, 1972, pp 1197-1203. Commerciallyavailable software programs may be used to assist in deriving reactivityratios from experimentally derived data. One example of such software isAspen Plus from Aspen Technology, Inc., Ten Canal Park, Cambridge, Mass.02141-2201 USA.

In a preferred embodiment, the polymers of the invention possess a mostprobable distribution of block lengths and block compositions. Preferredpolymers according to the invention are pseudo-block copolymerscontaining 4 or more blocks or segments including terminal blocks. Therespective blocks or segments need not be chemically similar, and moregenerally are characterized by a distribution of properties. Theinvention involves the concept of using chain shuttling as a way toprolong the lifetime of a polymer chain such that a substantial fractionof the polymer chains experience different polymerization conditions.Thus, instead of forming an intermolecular polymer blend, at least aportion of the polymer resulting from the present process comprisesdifferentiated polymer segments arranged intramolecularly. Because thevarious regions need not possess identical chemical or physicalproperties (that is, each differing region may be unique) and/or aportion of the polymer may comprise random monomer incorporation, theproduct is referred to as a pseudo-block copolymer.

In contrast with the previously discussed sequential polymerizationtechniques wherein no chain shuttling agent is utilized, polymerproducts can now be obtained according to the present invention byselecting highly active catalyst compositions capable of rapid transferof polymer segments both to and from a suitable chain shuttling agentsuch that polymer blocks or regions of the resulting catalyst possessdistinguishable polymer properties. Thus, due to the presence of a chainshuttling agent capable of rapid and efficient exchange of growingpolymer chains the growing polymer experiences discontinuous polymergrowth, such that intramolecular regions of the polymer are formed undermultiple polymerization conditions.

The following mathematical treatment of the resulting polymers is basedon theoretically derived parameters that are believed to apply to thepresent invented polymers and demonstrate that, especially in asteady-state, continuous reactor having differing polymerizationconditions to which the growing polymer is exposed, especially in arepetitive manner, the block lengths of the polymer being formed at anygiven point in the reactor will each conform to a most probabledistribution, derived in the following manner, wherein at any givenpoint in the reactor p_(i) is the probability of propagation withrespect to block sequences from catalyst i. The theoretical treatment isbased on standard assumptions and methods known in the art and used inpredicting the effects of polymerization kinetics on moleculararchitecture, including the use of mass action reaction rate expressionsthat are not affected by chain or block lengths, and the assumption thatpolymer chain growth is completed in a very short time compared to themean reactor residence time. Such methods have been previously disclosedin W. H. Ray, J. Macromol. Sci. Rev. Macromol. Chem., C8, 1 (1972) andA. E. Hamielec and J. F. MacGregor, “Polymer Reaction Engineering”, K.H. Reichert and W. Geisler, Eds., Hanser, Munich, 1983. In addition itis assumed each incidence of the chain shuttling reaction results in theformation of a new polymer block, regardless of which catalyst engagesin the shuttling, so that adjacent blocks formed by the same catalystare counted as different blocks. For catalyst i, the fraction ofsequences of length n being produced at any given point in the reactoris given by X_(i)[n], where n is an integer from 1 to infinityrepresenting the total number of monomer units in the block.

$\begin{matrix}\mspace{14mu} \\\;\end{matrix}\begin{matrix}{{X_{i}\lbrack n\rbrack} = {( {1 - p_{i}} )p_{i}^{({n - 1})}}} & {{most}\mspace{14mu}{probable}\mspace{14mu}{distribution}\mspace{14mu}{of}\mspace{14mu}{block}\mspace{14mu}{lengths}} \\{N_{i} = \frac{1}{1 - p_{i}}} & {{number}\mspace{14mu}{average}\mspace{14mu}{block}\mspace{14mu}{length}}\end{matrix}$

If more than one catalyst is present, at any given point in the reactoreach catalyst has a probability of propagation (p_(i)) and therefore hasa unique average block length and distribution for polymer being made atthat point. In a most preferred embodiment the probability ofpropagation is defined as:

$p_{i} = \frac{{Rp}\lbrack i\rbrack}{{{Rp}\lbrack i\rbrack} + {{Rt}\lbrack i\rbrack} + {{Rs}\lbrack i\rbrack} + \lbrack C_{i} \rbrack}$

-   -   for each catalyst i={1, 2 . . . }, where,

Rp[i]=Local rate of monomer consumption by catalyst i, (moles/L/time),

Rt[i]=Total rate of chain transfer and termination for catalyst i,(moles/L/time), and

Rs[i]=Local rate of chain shuttling with dormant polymer,(moles/L/time).

For a given point in the reactor the local monomer consumption orpolymer propagation rate, Rp[i], is defined using an apparent rateconstant, k_(pi) , multiplied by a total monomer concentration, [M], andmultiplied by the local concentration of catalyst i, [Ci], as follows:Rp[i]= k_(pi) [M][C_(i)]

For a given point in the reactor, the local chain transfer, termination,and shuttling rate is expressed below with local values for chaintransfer to hydrogen (H₂), beta hydride elimination, and chain transferto chain shuttling agent (CSA). The quantities [H₂] and [CSA] are localmolar concentrations and each subscripted k value is a rate constant forthe given point in the reactorRt[i]=k _(H2i)[H₂ ][C _(i) ]+k _(βi) [C _(i) ]+k _(ai)[CSA][C_(i)]

Dormant polymer chains are created when a polymer moiety transfers to aCSA and all CSA moieties that react are assumed to each be paired with adormant polymer chain. The rate of chain shuttling of dormant polymerwith catalyst i is given as follows, where [CSA_(f)] is the feedconcentration of CSA, and the quantity ([CSA_(f)]−[CSA]) represents theconcentration of dormant polymer chains:Rs[i]=k _(ai) [C _(i)]([CSA_(f)]−[CSA])

The overall block length distribution for the final effluent polymer isa sum of the local instantaneous block length distribution givenpreviously by X_(i)[n], weighted by the local polymer production ratefor catalyst i. This means that a greater diversity of polymerizationconditions will have a broadening affect on the overall block lengthdistribution.

Monomers

Suitable monomers for use in preparing the copolymers of the presentinvention include any addition polymerizable monomer, preferably anyolefin monomer, and most preferably ethylene and at least onecopolymerizable comonomer, propylene and at least one copolymerizablecomonomer, or 4-methyl-1-pentene and at least one copolymerizablecomonomer. Examples of suitable monomers include straight-chain orbranched α-olefins of 2 to 30, preferably 3 to 20 carbon atoms, such asethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexane,4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene,1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicosene; cycloolefinsof 3 to 30, preferably 3 to 20 carbon atoms, such as cyclopentene,cycloheptene, norbornene, 5-methyl-2-norbornene, tetracyclododecene, and2-methyl-1,4,5,8-dimethano-1,2,3,4,4a,5,8,8a-octahydronaphthalene; di-and poly-olefins, such as butadiene, isoprene, 4-methyl-1,3-pentadiene,1,3-pentadiene, 1,4-pentadiene, 1,5-hexadiene, 1,4-hexadiene,1,3-hexadiene, 1,3-octadiene, 1,4-octadiene, 1,5-octadiene,1,6-octadiene, 1,7-octadiene, ethylidene norbornene, vinyl norbornene,dicyclopentadiene, 7-methyl-1,6-octadiene,4-ethylidene-8-methyl-1,7-nonadiene, and 5,9-dimethyl-1,4,8-decatriene;aromatic vinyl compounds such as mono or poly alkylstyrenes (includingstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,o,p-dimethylstyrene, o-ethylstyrene, m-ethylstyrene and p-ethylstyrene),and functional group-containing derivatives, such as methoxystyrene,ethoxystyrene, vinylbenzoic acid, methyl vinylbenzoate, vinylbenzylacetate, hydroxystyrene, o-chlorostyrene, p-chlorostyrene,divinylbenzene, 3-phenylpropene, 4-phenylpropene and α-methylstyrene,vinylchloride, 1,2-difluoroethylene, 1,2-dichloroethylene,tetrafluoroethylene, and 3,3,3-trifluoro-1-propene.

Chain Shuttling Agents

The term, “shuttling agent” or “chain shuttling agent”, refers to acompound or mixture of compounds that is capable of causing polymeryltransfer between the various active catalyst sites under the conditionsof the polymerization. That is, transfer of a polymer fragment occursboth to and from an active catalyst site in a facile manner. In contrastto a shuttling agent, a “chain transfer agent” causes termination ofpolymer chain growth and amounts to a one-time transfer of growingpolymer from the catalyst to the transfer agent. Desirably, theintermediate formed between the chain shuttling agent and the polymerylchain is sufficiently stable that chain termination is relatively rare.Desirably, less than 10 percent, preferably less than 50 percent, morepreferably less than 75 percent and most desirably less than 90 percentof shuttling agent-polymeryl products are terminated prior to attaining3 distinguishable, intramolecular polymer segments or blocks.

While attached to the growing polymer chain, the shuttling agentdesirably does not alter the polymer structure or incorporate additionalmonomer. That is, the shuttling agent does not also possess significantcatalytic properties for the polymerization of interest. Rather, theshuttling agent forms a metal-alkyl or other type interaction with thepolymer moiety, for a time period such that a slightly different polymercomposition is formed after transfer of the polymer moiety back to anactive polymerization catalyst site. As a consequence, the subsequentlyformed polymer region possesses a distinguishable physical or chemicalproperty, such as a difference in comonomer composition distribution,crystallinity, density, tacticity, regio-error, or other property.Subsequent repetitions of the foregoing process can result in formationof segments or blocks having differing properties, or a repetition of apreviously formed polymer composition, depending on the rates ofpolymeryl exchange and transport within the reactor. The polymers of theinvention desirably are characterized by individual blocks or segmentshaving a continuously variable composition distribution. That is,adjacent blocks have slightly altered composition within the polymerchains. The composition distribution or other physical or chemicalproperty of the various blocks according to the present invention iscontinuously varying, due to the gradient or variation in one or moreprocess conditions between different regions of the reactor.

The foregoing process is schematically represented for a single catalystsystem in FIG. 1, where catalyst A, 10, is used to prepare a firstpolymer moiety, 12, under a first set of polymerization conditions. Thepolymerization is interrupted and the growing polymer transferred to achain shuttling agent B, the combination being illustrated as, 14, andat a subsequent time, back to a catalyst A now exposed to polymerizationconditions 2, said combination being identified as, 16. Polymerizationcondition 2 is different in at least one respect, preferably withrespect to comonomer/monomer ratio, compared to polymerization condition1. Polymerization commences under condition 2 but is again interruptedand the growing polymer transferred again to chain shuttling agent B,said new combination being illustrated as, 18, and subsequently, backonce again to catalyst A, now exposed to polymerization condition 3. Thegrowing polymer chain and active catalyst site are illustrated as, 20.Highly likely, polymerization condition 3 is dissimilar to bothpolymerization condition 1 and polymerization condition 2. Accordingly,it may be seen that multiple transfers of growing polymer may occurduring the process of the invention and polymer segments within the samepolymer are formed under multiple polymerization conditions. Ideally,the rate of chain shuttling is equivalent to or faster than the rate ofpolymer termination, even up to 10 or even 100 times faster than therate of polymer termination. This permits formation of multiple polymerblocks on the same time scale as polymer propagation.

By selecting different shuttling agents or mixtures of agents with acatalyst, by altering the comonomer composition, temperature, pressure,optional chain terminating agent such as H₂, or other reactionconditions in multiple regions of a reactor, polymer products havingsegments of continuously varying densities or comonomer concentrations,block lengths, block composition distributions, and/or otherdistinguishing property can be prepared. For example, if the activity ofthe shuttling agent is low relative to the catalyst polymer chainpropagation rate, the resulting copolymer will differ in compositiondistribution from a copolymer resulting from the use of a shuttlingagent that is very fast relative to polymer chain propagation. In theformer, the block lengths will tend to increase and possess greaterinternal variation compared to products made under the latterconditions. In a typical continuous solution polymerization reactor, thepolymerization conditions will be continuously shifting between twoextremes and the resulting polymer segments will reflect multipleslightly differing polymerization conditions. In addition, certainquantities of a conventional random copolymer may also be formedcoincident with formation of the pseudo-block copolymer of the presentinvention, resulting in a resin blend. If a relatively fast shuttlingagent is employed, a copolymer having shorter block lengths but moreuniform composition is obtained, with little formation of randomcopolymer. All of the blocks may be characterized as being continuouslytapering, both within individual blocks and over multiple blocks. Ineffect, a block copolymer having multiple, generally tapering blocks ora copolymer of continuously varying composition distribution is formed.By proper selection of both catalyst and shuttling agent, copolymerscontaining relatively large polymer segments or blocks approximatingtrue block copolymers or blends of the foregoing with more randomcopolymers can all be obtained.

A suitable composition comprising catalyst, cocatalyst, and a chainshuttling agent especially adapted for use herein can be selected bymeans of the following multi-step procedure:

I. One or more addition polymerizable, preferably olefin monomers arepolymerized using a mixture comprising a potential catalyst and apotential chain shuttling agent. This polymerization test is desirablyperformed using a batch or semi-batch reactor (that is, without resupplyof catalyst or shuttling agent), preferably with relatively constantmonomer concentration, operating under solution polymerizationconditions, typically using a molar ratio of catalyst to chain shuttlingagent from 1:5 to 1:500. After forming a suitable quantity of polymer,the reaction is terminated by addition of a catalyst poison and thepolymer's properties (Mw, Mn, and Mw/Mn or PDI) measured.

II. The foregoing polymerization and polymer testing are repeated forseveral different reaction times, providing a series of polymers havinga range of yields and PDI values.

III. Catalyst/chain shuttling agent pairs demonstrating significantpolymer transfer both to and from the chain shuttling agent arecharacterized by a polymer series wherein the minimum PDI is less than2.0, more preferably less than 1.5, and most preferably less than 1.3.Furthermore, if chain shuttling is occurring, the Mn of the polymer willincrease, preferably nearly linearly, as conversion is increased. Mostpreferred catalyst/shuttling agent pairs are those giving polymer Mn asa function of conversion (or polymer yield) fitting a line with astatistical precision (R²) of greater than 0.95, preferably greater than0.99.

Steps I-III are then carried out for one or more additional pairings ofpotential catalysts and/or putative shuttling agents.

In addition, it is preferable that the chain shuttling agent does notreduce the catalyst activity (measured in weight of polymer produced perweight of catalyst per unit time) by more than 60 percent, morepreferably such catalyst activity is not reduced by more than 20percent, and most preferably catalyst activity of the catalyst isincreased compared to the catalyst activity in the absence of a chainshuttling agent. A further consideration from a process viewpoint isthat the reaction mixture should possess as low a viscosity as possibleto reduce energy consumed in stirring the mixture. In this regard, amonofunctional shuttling agent is preferred to a difunctional agentwhich in turn is preferred to a trifunctional agent.

The foregoing test is readily adapted to rapid throughput screeningtechniques using automated reactors and analytic probes and to formationof polymer blocks having different distinguishing properties. Forexample, a number of potential chain shuttling agent candidates can bepre-identified or synthesized in situ by combination of variousorganometal compounds with various proton sources and the compound orreaction product added to a polymerization reaction employing an olefinpolymerization catalyst composition. Several polymerizations areconducted at varying molar ratios of shuttling agent to catalyst. As aminimum requirement, suitable shuttling agents are those that produce aminimum PDI of less than 2.0 in variable yield experiments as describedabove, while not significantly adversely affecting catalyst activity,and preferably improving catalyst activity, as above described.

Alternatively, it is also possible to detect desirablecatalyst/shuttling agent pairs by performing a series of polymerizationsunder standard batch reaction conditions and measuring the resultingnumber average molecular weights, PDI and polymer yield or productionrate. Suitable shuttling agents are characterized by lowering of theresultant Mn without significant broadening of PDI or loss of activity(reduction in yield or rate).

Regardless of the method for identifying, a priori, a shuttling agent,the term is meant to refer to a compound that is capable of preparingthe presently identified pseudo-block copolymers under thepolymerization conditions herein disclosed.

Suitable shuttling agents for use herein include Group 1, 2, 12 or 13metal compounds or complexes containing at least one C₁₋₂₀ hydrocarbylgroup, preferably hydrocarbyl substituted aluminum, gallium or zinccompounds containing from 1 to 12 carbons in each hydrocarbyl group, andreaction products thereof with a proton source. Preferred hydrocarbylgroups are alkyl groups, preferably linear or branched, C₂₋₈ alkylgroups. Most preferred shuttling agents for use in the present inventionare trialkyl aluminum and dialkyl zinc compounds, especiallytriethylaluminum, tri(i-propyl)aluminum, tri(1-butyl)aluminum,tri(n-hexyl)aluminum, tri(n-octyl)aluminum, triethylgallium, ordiethylzinc. Additional suitable shuttling agents include the reactionproduct or mixture formed by combining the foregoing organometalcompound, preferably a tri(C₁₋₈) alkyl aluminum or di(C₁₋₈)alkyl zinccompound, especially triethylaluminum, tri(i-propyl) aluminum,tri(1-butyl)aluminum, tri(n-hexyl)aluminum, tri(n-octyl)aluminum, ordiethylzinc, with less than a stoichiometric quantity (relative to thenumber of hydrocarbyl groups) of a secondary amine or a hydroxylcompound, especially bis(trimethylsilyl)amine,t-butyl(dimethyl)siloxane, 2-hydroxymethylpyridine, di(n-pentyl)amine,2,6-di(t-butyl)phenol, ethyl(1-naphthyl)amine,bis(2,3,6,7-dibenzo-1-azacycloheptaneamine), or 2,6-diphenylphenol.Desirably, sufficient amine or hydroxyl reagent is used such that onehydrocarbyl group remains per metal atom. The primary reaction productsof the foregoing combinations most desired for use in the presentinvention as shuttling agents are n-octylaluminumdi(bis(trimethylsilyl)amide), i-propylaluminumbis(dimethyl(t-butyl)siloxide), and n-octylaluminumdi(pyridinyl-2-methoxide), i-butylaluminumbis(dimethyl(t-butyl)siloxane), i-butylaluminumbis(di(trimethylsilyl)amide), n-octylaluminum di(pyridine-2-methoxide),i-butylaluminum bis(di(n-pentyl)amide), n-octylaluminumbis(2,6-di-t-butylphenoxide), n-octylaluminumdi(ethyl(1-naphthyl)amide), ethylaluminum bis(t-butyldimethylsiloxide),ethylaluminum di(bis(trimethylsilyl)amide), ethylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(2,3,6,7-dibenzo-1-azacycloheptaneamide), n-octylaluminumbis(dimethyl(t-butyl)siloxide, ethylzinc (2,6-diphenylphenoxide), andethylzinc (t-butoxide).

Preferred shuttling agents possess the highest transfer rates of polymertransfer as well as the highest transfer efficiencies (reducedincidences of chain termination). Such shuttling agents may be used inreduced concentrations and still achieve the desired degree ofshuttling. In addition, such shuttling agents result in production ofthe shortest possible polymer block lengths. Highly desirably, chainshuttling agents with a single exchange site are employed due to thefact that the effective molecular weight of the polymer in the reactoris lowered, thereby reducing viscosity of the reaction mixture andconsequently reducing operating costs.

Catalysts

Suitable catalysts for use herein include any compound or combination ofcompounds that is adapted for preparing polymers of the desiredcomposition or type. Both heterogeneous and homogeneous catalysts may beemployed. Examples of heterogeneous catalysts include the well knownZiegler-Natta compositions, especially Group 4 metal halides supportedon Group 2 metal halides or mixed halides and alkoxides and the wellknown chromium or vanadium based catalysts. Preferably however, for easeof use and for production of narrow molecular weight polymer segments insolution, the catalysts for use herein are homogeneous catalystscomprising a relatively pure organometallic compound or metal complex,especially compounds or complexes based on metals selected from Groups3-10 or the Lanthanide series of the Periodic Table of the Elements.

Metal complexes for use herein include complexes of transition metalsselected from Groups 3 to 15 of the Periodic Table of the Elementscontaining one or more delocalized, π-bonded ligands or polyvalent Lewisbase ligands. Examples include metallocene, half-metallocene,constrained geometry, and polyvalent pyridylamine, or otherpolychelating base complexes. The complexes are generically depicted bythe formula: MK_(k)X_(x)Z_(z), or a dimer thereof, wherein

M is a metal selected from Groups 3-15, preferably 3-10, more preferably4-10, and most preferably Group 4 of the Periodic Table of the Elements;

K independently each occurrence is a group containing delocalized7′-electrons or one or more electron pairs through which K is bound toM, said K group containing up to 50 atoms not counting hydrogen atoms,optionally two or more K groups may be joined together forming a bridgedstructure, and further optionally one or more K groups may be bound toZ, to X or to both Z and X;

X independently each occurrence is a monovalent, anionic moiety havingup to 40 non-hydrogen atoms, optionally one or more X groups may bebonded together thereby forming a divalent or polyvalent anionic group,and, further optionally, one or more X groups and one or more Z groupsmay be bonded together thereby forming a moiety that is both covalentlybound to M and coordinated thereto;

Z independently each occurrence is a neutral, Lewis base donor ligand ofup to 50 non-hydrogen atoms containing at least one unshared electronpair through which Z is coordinated to M;

k is an integer from 0 to 3;

x is an integer from 1 to 4;

z is a number from 0 to 3; and

the sum, k+x, is equal to the formal oxidation state of M.

Suitable metal complexes include those containing from 1 to 3 π-bondedanionic or neutral ligand groups, which may be cyclic or non-cyclicdelocalized π-bonded anionic ligand groups. Exemplary of such π-bondedgroups are conjugated or nonconjugated, cyclic or non-cyclic diene anddienyl groups, allyl groups, boratabenzene groups, phosphole, and arenegroups. By the term “π-bonded” is meant that the ligand group is bondedto the transition metal by a sharing of electrons from a partiallydelocalized π-bond.

Each atom in the delocalized π-bonded group may independently besubstituted with a radical selected from the group consisting ofhydrogen, halogen, hydrocarbyl, halohydrocarbyl, hydrocarbyl-substitutedheteroatoms wherein the heteroatom is selected from Group 14-16 of thePeriodic Table of the Elements, and such hydrocarbyl-substitutedheteroatom radicals further substituted with a Group 15 or 16 heteroatom containing moiety. In addition two or more such radicals maytogether form a fused ring system, including partially or fullyhydrogenated fused ring systems, or they may form a metallocycle withthe metal. Included within the term “hydrocarbyl” are C₁₋₂₀ straight,branched and cyclic alkyl radicals, C₆₋₂₀ aromatic radicals, C₇₋₂₀alkyl-substituted aromatic radicals, and C₇₋₂₀ aryl-substituted alkylradicals. Suitable hydrocarbyl-substituted heteroatom radicals includemono-, di- and tri-substituted radicals of boron, silicon, germanium,nitrogen, phosphorus or oxygen wherein each of the hydrocarbyl groupscontains from 1 to 20 carbon atoms. Examples include N,N-dimethylamino,pyrrolidinyl, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl,methyldi(t-butyl)silyl, triphenylgermyl, and trimethylgermyl groups.Examples of Group 15 or 16 hetero atom containing moieties includeamino, phosphino, alkoxy, or alkylthio moieties or divalent derivativesthereof, for example, amide, phosphide, alkyleneoxy or alkylenethiogroups bonded to the transition metal or Lanthanide metal, and bonded tothe hydrocarbyl group, π-bonded group, or hydrocarbyl-substitutedheteroatom.

Examples of suitable anionic, delocalized π-bonded groups includecyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl,tetrahydrofluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl,dihydroanthracenyl, hexahydroanthracenyl, decahydroanthracenyl groups,phosphole, and boratabenzyl groups, as well as inertly substitutedderivatives thereof, especially C₁₋₁₀ hydrocarbyl-substituted ortris(C₁₋₁₀ hydrocarbyl)silyl-substituted derivatives thereof. Preferredanionic delocalized π-bonded groups are cyclopentadienyl,pentamethylcyclopentadienyl, tetramethylcyclopentadienyl,tetramethylsilylcyclopentadienyl, indenyl, 2,3-dimethylindenyl,fluorenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl,tetrahydrofluorenyl, octahydrofluorenyl, 1-indacenyl,3-pyrrolidinoinden-1-yl, 3,4-(cyclopenta(1)phenanthren-1-yl, andtetrahydroindenyl.

The boratabenzenyl ligands are anionic ligands which are boroncontaining analogues to benzene. They are previously known in the arthaving been described by G. Herberich, et al., in Organometallics, 14,1, 471-480 (1995). Preferred boratabenzenyl ligands correspond to theformula:

wherein R¹ is an inert substituent, preferably selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, halo or germyl, said R¹having up to 20 atoms not counting hydrogen, and optionally two adjacentR¹ groups may be joined together. In complexes involving divalentderivatives of such delocalized π-bonded groups one atom thereof isbonded by means of a covalent bond or a covalently bonded divalent groupto another atom of the complex thereby forming a bridged system.

Phospholes are anionic ligands that are phosphorus containing analoguesto a cyclopentadienyl group. They are previously known in the art havingbeen described by WO 98/50392, and elsewhere. Preferred phospholeligands correspond to the formula:

wherein R¹ is as previously defined.

Preferred transition metal complexes for use herein correspond to theformula: MK_(k)X_(x)Z_(z), or a dimer thereof, wherein:

M is a Group 4 metal;

K is a group containing delocalized π-electrons through which K is boundto M, said K group containing up to 50 atoms not counting hydrogenatoms, optionally two K groups may be joined together forming a bridgedstructure, and further optionally one K may be bound to X or Z;

X each occurrence is a monovalent, anionic moiety having up to 40non-hydrogen atoms, optionally one or more X and one or more K groupsare bonded together to form a metallocycle, and further optionally oneor more X and one or more Z groups are bonded together thereby forming amoiety that is both covalently bound to M and coordinated thereto;

Z independently each occurrence is a neutral, Lewis base donor ligand ofup to 50 non-hydrogen atoms containing at least one unshared electronpair through which Z is coordinated to M;

k is an integer from 0 to 3;

x is an integer from 1 to 4;

z is a number from 0 to 3; and

the sum, k+x, is equal to the formal oxidation state of M.

Preferred complexes include those containing either one or two K groups.The latter complexes include those containing a bridging group linkingthe two K groups. Preferred bridging groups are those corresponding tothe formula (ER′₂)_(e) wherein E is silicon, germanium, tin, or carbon,R′ independently each occurrence is hydrogen or a group selected fromsilyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R′having up to 30 carbon or silicon atoms, and e is 1 to 8. Preferably, R′independently each occurrence is methyl, ethyl, propyl, benzyl,tert-butyl, phenyl, methoxy, ethoxy or phenoxy.

Examples of the complexes containing two K groups are compoundscorresponding to the formula:

wherein:

M is titanium, zirconium or hafnium, preferably zirconium or hafnium, inthe +2 or +4 formal oxidation state;

R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R³ having up to 20 non-hydrogen atoms, oradjacent R³ groups together form a divalent derivative (that is, ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system, and

X″ independently each occurrence is an anionic ligand group of up to 40non-hydrogen atoms, or two X″ groups together form a divalent anionicligand group of up to 40 non-hydrogen atoms or together are a conjugateddiene having from 4 to 30 non-hydrogen atoms bound by means ofdelocalized π-electrons to M, whereupon M is in the +2 formal oxidationstate, and

R′, E and e are as previously defined.

Exemplary bridged ligands containing two π-bonded groups are:dimethylbis(cyclopentadienyl)silane,dimethylbis(tetramethylcyclopentadienyl)silane,dimethylbis(2-ethylcyclopentadien-1-yl)silane,dimethylbis(2-t-butylcyclopentadien-1-yl)silane,2,2-bis(tetramethylcyclopentadienyl)propane,dimethylbis(inden-1-yl)silane, dimethylbis(tetrahydroinden-1-yl)silane,dimethylbis(fluoren-1-yl)silane,dimethylbis(tetrahydrofluoren-1-yl)silane,dimethylbis(2-methyl-4-phenylinden-1-yl)-silane,dimethylbis(2-methylinden-1-yl)silane,dimethyl(cyclopentadienyl)(fluoren-1-yl)silane,dimethyl(cyclopentadienyl)(octahydrofluoren-1-yl)silane,dimethyl(cyclopentadienyl)(tetrahydrofluoren-1-yl)silane,(1,1,2,2-tetramethy)-1,2-bis(cyclopentadienyl)disilane,(1,2-bis(cyclopentadienyl)ethane, anddimethyl(cyclopentadienyl)-1-(fluoren-1-yl)methane.

Preferred X″ groups are selected from hydride, hydrocarbyl, silyl,germyl, halohydrocarbyl, halosilyl, silylhydrocarbyl andaminohydrocarbyl groups, or two X″ groups together form a divalentderivative of a conjugated diene or else together they form a neutral,α-bonded, conjugated diene. Most preferred X″ groups are C₁₋₂₀hydrocarbyl groups.

Examples of metal complexes of the foregoing formula suitable for use inthe present invention include:

-   bis(cyclopentadienyl)zirconiumdimethyl,-   bis(cyclopentadienyl)zirconium dibenzyl,-   bis(cyclopentadienyl)zirconium methyl benzyl,-   bis(cyclopentadienyl)zirconium methyl phenyl,-   bis(cyclopentadienyl)zirconiumdiphenyl,-   bis(cyclopentadienyl)titanium-allyl,-   bis(cyclopentadienyl)zirconiummethylmethoxide,-   bis(cyclopentadienyl)zirconiummethylchloride,-   bis(pentamethylcyclopentadienyl)zirconiumdimethyl,-   bis(pentamethylcyclopentadienyl)titaniumdimethyl,-   bis(indenyl)zirconiumdimethyl,-   indenylfluorenylzirconiumdimethyl,-   bis(indenyl)zirconiummethyl(2-(dimethylamino)benzyl),-   bis(indenyl)zirconiummethyltrimethylsilyl,-   bis(tetrahydroindenyl)zirconiummethyltrimethylsilyl,-   bis(pentamethylcyclopentadienyl)zirconiummethylbenzyl,-   bis(pentamethylcyclopentadienyl)zirconiumdibenzyl,-   bis(pentamethylcyclopentadienyl)zirconiummethylmethoxide,-   bis(pentamethylcyclopentadienyl)zirconiummethylchloride,-   bis(methylethylcyclopentadienyl)zirconiumdimethyl,-   bis(butylcyclopentadienyl)zirconiumdibenzyl,-   bis(t-butylcyclopentadienyl)zirconiumdimethyl,-   bis(ethyltetramethylcyclopentadienyl)zirconiumdimethyl,-   bis(methylpropylcyclopentadienyl)zirconiumdibenzyl,-   bis(trimethylsilylcyclopentadienyl)zirconiumdibenzyl,-   dimethylsilylbis(cyclopentadienyl)zirconiumdimethyl,    dimethylsilylbis(tetramethylcyclopentadienyl)titanium (III) allyl-   dimethylsilylbis(t-butylcyclopentadienyl)zirconiumdichloride,-   dimethylsilylbis(n-butylcyclopentadienyl)zirconiumdichloride,-   (methylenebis(tetramethylcyclopentadienyl)titanium(III)    2-(dimethylamino)benzyl,-   (methylenebis(n-butylcyclopentadienyl)titanium(III)    2-(dimethylamino)benzyl,-   dimethylsilylbis(indenyl)zirconiumbenzylchloride,-   dimethylsilylbis(2-methylindenyl)zirconiumdimethyl,-   dimethylsilylbis(2-methyl-4-phenylindenyl)zirconiumdimethyl,-   dimethylsilylbis(2-methylindenyl)zirconium-1,4-diphenyl-1,3-butadiene,-   dimethylsilylbis(2-methyl-4-phenylindenyl)zirconium (II)    1,4-diphenyl-1,3-butadiene,-   dimethylsilylbis(tetrahydroindenyl)zirconium(II)    1,4-diphenyl-1,3-butadiene,-   dimethylsilylbis(tetramethylcyclopentadienyl)zirconium dimethyl-   dimethylsilylbis(fluorenyl)zirconiumdimethyl,-   dimethylsilyl-bis(tetrahydrofluorenyl)zirconium bis(trimethylsilyl),-   (isopropylidene)(cyclopentadienyl)(fluorenyl)zirconiumdibenzyl, and-   dimethylsilyl(tetramethylcyclopentadienyl)(fluorenyl)zirconium    dimethyl.

A further class of metal complexes utilized in the present inventioncorresponds to the preceding formula: MKZ_(z)X_(x), or a dimer thereof,wherein M, K, X, x and z are as previously defined, and Z is asubstituent of up to 50 non-hydrogen atoms that together with K forms ametallocycle with M.

Preferred Z substituents include groups containing up to 30 non-hydrogenatoms comprising at least one atom that is oxygen, sulfur, boron or amember of Group 14 of the Periodic Table of the Elements directlyattached to K, and a different atom, selected from the group consistingof nitrogen, phosphorus, oxygen or sulfur that is covalently bonded toM.

More specifically this class of Group 4 metal complexes used accordingto the present invention includes “constrained geometry catalysts”corresponding to the formula:

wherein:

M is titanium or zirconium, preferably titanium in the +2, +3, or +4formal oxidation state;

K¹ is a delocalized, π-bonded ligand group optionally substituted withfrom 1 to 5 R² groups,

R² in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R² having up to 20 non-hydrogen atoms, oradjacent R² groups together form a divalent derivative (that is, ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system,

each X is a halo, hydrocarbyl, hydrocarbyloxy or silyl group, said grouphaving up to 20 non-hydrogen atoms, or two X groups together form aneutral C₅₋₃₀ conjugated diene or a divalent derivative thereof;

x is 1 or 2;

Y is —O—, —S—, —NR′—, —PR′—; and

X¹ is SiR′₂, CR′₂, SiR′₂SiR′₂, CR′₂CR′₂, CR′═CR′, CR′₂SiR′₂, or GeR′₂,wherein

R′ independently each occurrence is hydrogen or a group selected fromsilyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R′having up to 30 carbon or silicon atoms.

Specific examples of the foregoing constrained geometry metal complexesinclude compounds corresponding to the formula:

wherein,

Ar is an aryl group of from 6 to 30 atoms not counting hydrogen;

R⁴ independently each occurrence is hydrogen, Ar, or a group other thanAr selected from hydrocarbyl, trihydrocarbylsilyl, trihydrocarbylgermyl,halide, hydrocarbyloxy, trihydrocarbylsiloxy,bis(trihydrocarbylsilyl)amino, di(hydrocarbyl)amino,hydrocarbadiylamino, hydrocarbylimino, di(hydrocarbyl)phosphino,hydrocarbadiylphosphino, hydrocarbylsulfido, halo-substitutedhydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl,trihydrocarbylsilyl-substituted hydrocarbyl,trihydrocarbylsiloxy-substituted hydrocarbyl,bis(trihydrocarbylsilyl)amino-substituted hydrocarbyl,di(hydrocarbyl)amino-substituted hydrocarbyl,hydrocarbyleneamino-substituted hydrocarbyl,di(hydrocarbyl)phosphino-substituted hydrocarbyl,hydrocarbylenephosphino-substituted hydrocarbyl, orhydrocarbylsulfido-substituted hydrocarbyl, said R group having up to 40atoms not counting hydrogen atoms, and optionally two adjacent R⁴ groupsmay be joined together forming a polycyclic fused ring group;

M is titanium;

X¹ is SiR⁶ ₂, CR⁶ ₂, SiR⁶ ₂SiR⁶ ₂, CR⁶ ₂CR⁶ ₂, CR⁶═CR⁶, CR⁶ ₂SiR⁶ ₂,BR⁶, BR⁶L″, or GeR⁶ ₂;

Y is —O—, —S—, —NR⁵—, —PR⁵—; —NR², or —PR⁵ ₂;

R⁵, independently each occurrence, is hydrocarbyl, trihydrocarbylsilyl,or trihydrocarbylsilylhydrocarbyl, said R⁵ having up to 20 atoms otherthan hydrogen, and optionally two R⁵ groups or R⁵ together with Y or Zform a ring system;

R⁶, independently each occurrence, is hydrogen, or a member selectedfrom hydrocarbyl, hydrocarbyloxy, silyl, halogenated alkyl, halogenatedaryl, —NR⁵ ₂, and combinations thereof, said R⁶ having up to 20non-hydrogen atoms, and optionally, two R¹ groups or R¹ together with Zforms a ring system;

Z is a neutral diene or a monodentate or polydentate Lewis baseoptionally bonded to R⁵, R⁶, or X;

X is hydrogen, a monovalent anionic ligand group having up to 60 atomsnot counting hydrogen, or two X groups are joined together therebyforming a divalent ligand group;

x is 1 or 2; and

z is 0, 1 or 2.

Preferred examples of the foregoing metal complexes are substituted atboth the 3- and 4-positions of a cyclopentadienyl or indenyl group withan Ar group.

Examples of the foregoing metal complexes include:

-   (3-phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,3-diphenyl-1,3-butadiene;-   (3-(pyrrol-1-yl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-(pyrrol-1-yl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-(pyrrol-1-yl)cyclopentadien-1-yl))dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3-(1-methylpyrrol-3-yl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-(1-methylpyrrol-3-yl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-(1-methylpyrrol-3-yl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3,4-diphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3,4-diphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3,4-diphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,3-pentadiene;-   (3-(3-N,N-dimethylamino)phenyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-(3-N,N-dimethylamino)phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-(3-N,N-dimethylamino)phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3-(4-methoxyphenyl)-4-methylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-(4-methoxyphenyl)-4-phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-4-methoxyphenyl)-4-phenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3-phenyl-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-phenyl-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-phenyl-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   2-methyl-(3,4-di(4-methylphenyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   2-methyl-(3,4-di(4-methylphenyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   2-methyl-(3,4-di(4-methylphenyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   ((2,3-diphenyl)-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silane    titanium dichloride,-   ((2,3-diphenyl)-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silane    titanium dimethyl,-   ((2,3-diphenyl)-4-(N,N-dimethylamino)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (2,3,4-triphenyl-5-methylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (2,3,4-triphenyl-5-methylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (2,3,4-triphenyl-5-methylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (3-phenyl-4-methoxycyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (2,3-diphenyl-4-(n-butyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (2,3-diphenyl-4-(n-butyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl,-   (2,3-diphenyl-4-(n-butyl)cyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene;-   (2,3,4,5-tetraphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dichloride,-   (2,3,4,5-tetraphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium    dimethyl, and-   (2,3,4,5-tetraphenylcyclopentadien-1-yl)dimethyl(t-butylamido)silanetitanium (II)    1,4-diphenyl-1,3-butadiene.

Additional examples of suitable metal complexes for use herein arepolycyclic complexes corresponding to the formula:

where M is titanium in the +2, +3 or +4 formal oxidation state;

R⁷ independently each occurrence is hydride, hydrocarbyl, silyl, germyl,halide, hydrocarbyloxy, hydrocarbylsiloxy, hydrocarbylsilylamino,di(hydrocarbyl)amino, hydrocarbyleneamino, di(hydrocarbyl)phosphino,hydrocarbylene-phosphino, hydrocarbylsulfido, halo-substitutedhydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl, silyl-substitutedhydrocarbyl, hydrocarbylsiloxy-substituted hydrocarbyl,hydrocarbylsilylamino-substituted hydrocarbyl,di(hydrocarbyl)amino-substituted hydrocarbyl,hydrocarbyleneamino-substituted hydrocarbyl,di(hydrocarbyl)phosphino-substituted hydrocarbyl,hydrocarbylene-phosphino-substituted hydrocarbyl, orhydrocarbylsulfido-substituted hydrocarbyl, said R⁷ group having up to40 atoms not counting hydrogen, and optionally two or more of theforegoing groups may together form a divalent derivative;

R⁸ is a divalent hydrocarbylene- or substituted hydrocarbylene groupforming a fused system with the remainder of the metal complex, said R⁸containing from 1 to 30 atoms not counting hydrogen;

X^(a) is a divalent moiety, or a moiety comprising one σ-bond and aneutral two electron pair able to form a coordinate-covalent bond to M,said X^(a) comprising boron, or a member of Group 14 of the PeriodicTable of the Elements, and also comprising nitrogen, phosphorus, sulfuror oxygen;

X is a monovalent anionic ligand group having up to 60 atoms exclusiveof the class of ligands that are cyclic, delocalized, π-bound ligandgroups and optionally two X groups together form a divalent ligandgroup;

Z independently each occurrence is a neutral ligating compound having upto 20 atoms;

x is 0, 1 or 2; and

z is zero or 1.

Preferred examples of such complexes are 3-phenyl-substituteds-indecenyl complexes corresponding to the formula:

2,3-dimethyl-substituted s-indecenyl complexes corresponding to theformulas:

or 2-methyl-substituted s-indecenyl complexes corresponding to theformula:

Additional examples of metal complexes that are usefully employedaccording to the present invention include those of the formula:

Specific metal complexes include:

-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,4-diphenyl-1,3-butadiene,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,3-pentadiene,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 2-(N,N-dimethylamino)benzyl,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dichloride,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dimethyl,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dibenzyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,4-diphenyl-1,3-butadiene,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,3-pentadiene,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (III) 2-(N,N-dimethylamino)benzyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dichloride,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dimethyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-1-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dibenzyl,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,4-diphenyl-1,3-butadiene,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,3-pentadiene,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (III) 2-(N,N-dimethylamino)benzyl,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dichloride,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dimethyl,-   (8-methylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dibenzyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,4-diphenyl-1,3-butadiene,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (II) 1,3-pentadiene,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (III) 2-(N,N-dimethylamino)benzyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dichloride,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dimethyl,-   (8-difluoromethylene-1,8-dihydrodibenzo[e,h]azulen-2-yl)-N-(1,1-dimethylethyl)dimethylsilanamide    titanium (IV) dibenzyl, and mixtures thereof, especially mixtures of    positional isomers.

Further illustrative examples of metal complexes for use according tothe present invention correspond to the formula:

where M is titanium in the +2, +3 or +4 formal oxidation state;

T is —NR⁹— or —O—;

R⁹ is hydrocarbyl, silyl, germyl, dihydrocarbylboryl, or halohydrocarbylor up to 10 atoms not counting hydrogen;

R¹⁰ independently each occurrence is hydrogen, hydrocarbyl,trihydrocarbylsilyl, trihydrocarbylsilylhydrocarbyl, germyl, halide,hydrocarbyloxy, hydrocarbylsiloxy, hydrocarbylsilylamino,di(hydrocarbyl)amino, hydrocarbyleneamino, di(hydrocarbyl)phosphino,hydrocarbylene-phosphino, hydrocarbylsulfido, halo-substitutedhydrocarbyl, hydrocarbyloxy-substituted hydrocarbyl, silyl-substitutedhydrocarbyl, hydrocarbylsiloxy-substituted hydrocarbyl,hydrocarbylsilylamino-substituted hydrocarbyl,di(hydrocarbyl)amino-substituted hydrocarbyl,hydrocarbyleneamino-substituted hydrocarbyl,di(hydrocarbyl)phosphino-substituted hydrocarbyl,hydrocarbylenephosphino-substituted hydrocarbyl, orhydrocarbylsulfido-substituted hydrocarbyl, said R¹⁰ group having up to40 atoms not counting hydrogen atoms, and optionally two or more of theforegoing adjacent R¹⁰ groups may together form a divalent derivativethereby forming a saturated or unsaturated fused ring;

X^(a) is a divalent moiety lacking in delocalized n-electrons, or such amoiety comprising one σ-bond and a neutral two electron pair able toform a coordinate-covalent bond to M, said X′ comprising boron, or amember of Group 14 of the Periodic Table of the Elements, and alsocomprising nitrogen, phosphorus, sulfur or oxygen;

X is a monovalent anionic ligand group having up to 60 atoms exclusiveof the class of ligands that are cyclic ligand groups bound to M throughdelocalized π-electrons or two X groups together are a divalent anionicligand group;

Z independently each occurrence is a neutral ligating compound having upto 20 atoms;

x is 0, 1, 2, or 3; and

z is 0 or 1.

Highly preferably T is ═N(CH₃), X is halo or hydrocarbyl, x is 2, X′ isdimethylsilane, z is 0, and R¹⁰ each occurrence is hydrogen, ahydrocarbyl, hydrocarbyloxy, dihydrocarbylamino, hydrocarbyleneamino,dihydrocarbylamino-substituted hydrocarbyl group, orhydrocarbyleneamino-substituted hydrocarbyl group of up to 20 atoms notcounting hydrogen, and optionally two R¹⁰ groups may be joined together.

Illustrative metal complexes of the foregoing formula that may beemployed in the practice of the present invention further include thefollowing compounds:

-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,3-pentadiene,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (III)    2-(N,N-dimethylamino)benzyl,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dichloride,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dimethyl,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dibenzyl,-   (t-butylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    bis(trimethylsilyl),-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,3-pentadiene,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (III)    2-(N,N-dimethylamino)benzyl,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dichloride,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dimethyl,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dibenzyl,-   (cyclohexylamido)dimethyl-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    bis(trimethylsilyl),-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,3-pentadiene,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (III)    2-(N,N-dimethylamino)benzyl,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dichloride,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dimethyl,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dibenzyl,-   (t-butylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    bis(trimethylsilyl),-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (II)    1,3-pentadiene,-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (III)    2-(N,N-dimethylamino)benzyl,-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dichloride,-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dimethyl,-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    dibenzyl; and-   (cyclohexylamido)di(p-methylphenyl)-[6,7]benzo-[4,5:2′,3′](1-methylisoindol)-(3H)-indene-2-yl)silanetitanium (IV)    bis(trimethylsilyl).

Illustrative Group 4 metal complexes that may be employed in thepractice of the present invention further include:

-   (tert-butylamido)(1,1-dimethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(1,1,2,3-tetramethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)    dimethylsilanetitanium dibenzyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium    dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyltitanium    dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-indenyl)dimethylsilanetitanium    dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethlylsilane    titanium (III) 2-(dimethylamino)benzyl;-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (III)    allyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (III)    2,4-dimethylpentadienyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)    2,4-hexadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    2,3-dimethyl-1,3-butadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    isoprene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    2,3-dimethyl-1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    isoprene-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    dimethyl-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    dibenzyl-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    dimethyl,-   (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)    dibenzyl,-   (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)    1,4-diphenyl-1,3-butadiene,-   (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)    1,3-pentadiene,-   (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)    2,4-hexadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium (IV)    1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (IV)    2,3-dimethyl-1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (IV)    isoprene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium (II)    1,4-dibenzyl-1,3-butadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (II)    2,4-hexadiene,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium (II)    3-methyl-1,3-pentadiene,-   (tert-butylamido)(2,4-dimethylpentadien-3-yl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(6,6-dimethylcyclohexadienyl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(1,1-dimethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl,-   (tert-butylamido)(1,1,2,3-tetramethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl    methylphenylsilanetitanium (IV) dimethyl,-   (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl    methylphenylsilanetitanium (II) 1,4-diphenyl-1,3-butadiene,-   1-(tert-butylamido)-2-(tetramethyl-η⁵-cyclopentadienyl)ethanediyltitanium (IV)    dimethyl, and-   1-(tert-butylamido)-2-(tetramethyl-η⁵-cyclopentadienyl)ethanediyl-titanium (II)    1,4-diphenyl-1,3-butadiene.

Other delocalized, π-bonded complexes, especially those containing otherGroup 4 metals, will, of course, be apparent to those skilled in theart, and are disclosed among other places in: WO 03/78480, WO 03/78483,WO 02/92610, WO 02/02577, US 2003/0004286 and U.S. Pat. Nos. 6,515,155,6,555,634, 6,150,297, 6,034,022, 6,268,444, 6,015,868, 5,866,704, and5,470,993.

Additional examples of metal complexes that are usefully employed hereininclude polyvalent Lewis base compounds corresponding to the formula:

wherein T^(b) is a bridging group, preferably containing 2 or more atomsother than hydrogen,

X^(b) and Y^(b) are each independently selected from the groupconsisting of nitrogen, sulfur, oxygen and phosphorus; more preferablyboth X^(b) and Y^(b) are nitrogen,

R^(b) and R^(b′) independently each occurrence are hydrogen or C₁₋₅₀hydrocarbyl groups optionally containing one or more heteroatoms orinertly substituted derivative thereof. Non-limiting examples ofsuitable R^(b) and R^(b′) groups include alkyl, alkenyl, aryl, aralkyl,(poly)alkylaryl and cycloalkyl groups, as well as nitrogen, phosphorus,oxygen and halogen substituted derivatives thereof. Specific examples ofsuitable Rb and Rb′ groups include methyl, ethyl, isopropyl, octyl,phenyl, 2,6-dimethylphenyl, 2,6-di(isopropyl)phenyl,2,4,6-trimethylphenyl, pentafluorophenyl, 3,5-trifluoromethylphenyl, andbenzyl;

g is 0 or 1;

M^(b) is a metallic element selected from Groups 3 to 15, or theLanthanide series of the Periodic Table of the Elements. Preferably, Mbis a Group 3-13 metal, more preferably M^(b) is a Group 4-10 metal;

L^(b) is a monovalent, divalent, or trivalent anionic ligand containingfrom 1 to 50 atoms, not counting hydrogen. Examples of suitable L^(b)groups include halide; hydride; hydrocarbyl, hydrocarbyloxy;di(hydrocarbyl)amido, hydrocarbyleneamido, di(hydrocarbyl)phosphido;hydrocarbylsulfido; hydrocarbyloxy, tri(hydrocarbylsilyl)alkyl; andcarboxylates. More preferred L^(b) groups are C₁₋₂₀ alkyl, C₇₋₂₀aralkyl, and chloride;

h is an integer from 1 to 6, preferably from 1 to 4, more preferablyfrom 1 to 3, and j is 1 or 2, with the value h×j selected to providecharge balance;

Z^(b) is a neutral ligand group coordinated to M^(b), and containing upto 50 atoms not counting hydrogen Preferred Z^(b) groups includealiphatic and aromatic amines, phosphines, and ethers, alkenes,alkadienes, and inertly substituted derivatives thereof. Suitable inertsubstituents include halogen, alkoxy, aryloxy, alkoxycarbonyl,aryloxycarbonyl, di(hydrocarbyl)amine, tri(hydrocarbyl)silyl, andnitrile groups. Preferred Z^(b) groups include triphenylphosphine,tetrahydrofuran, pyridine, and 1,4-diphenylbutadiene;

f is an integer from 1 to 3;

two or three of T^(b), R^(b) and R^(b′) may be joined together to form asingle or multiple ring structure;

h is an integer from 1 to 6, preferably from 1 to 4, more preferablyfrom 1 to 3;

indicates any form of electronic interaction comprising a net coulombicattraction, especially coordinate or covalent bonds, including multiplebonds;

arrows signify coordinate bonds; and

dotted lines indicate optional double bonds.

In one embodiment, it is preferred that R^(b) have relatively low sterichindrance with respect to X^(b). In this embodiment, most preferredR^(b) groups are straight chain alkyl groups, straight chain alkenylgroups, branched chain alkyl groups wherein the closest branching pointis at least 3 atoms removed from X^(b), and halo, dihydrocarbylamino,alkoxy or trihydrocarbylsilyl substituted derivatives thereof. Highlypreferred R^(b) groups in this embodiment are C₁₋₈ straight chain alkylgroups.

At the same time, in this embodiment R^(b′) preferably has relativelyhigh steric hindrance with respect to Y^(b). Non-limiting examples ofsuitable R^(b′) groups for this embodiment include alkyl or alkenylgroups containing one or more secondary or tertiary carbon centers,cycloalkyl, aryl, alkaryl, aliphatic or aromatic heterocyclic groups,organic or inorganic oligomeric, polymeric or cyclic groups, and halo,dihydrocarbylamino, alkoxy or trihydrocarbylsilyl substitutedderivatives thereof. Preferred R^(b′) groups in this embodiment containfrom 3 to 40, more preferably from 3 to 30, and most preferably from 4to 20 atoms not counting hydrogen and are branched or cyclic.

Examples of preferred T^(b) groups are structures corresponding to thefollowing formulas:

wherein

Each R^(d) is C₁₋₁₀ hydrocarbyl group, preferably methyl, ethyl,n-propyl, i-propyl, t-butyl, phenyl, 2,6-dimethylphenyl, benzyl, ortolyl. Each R^(e) is C₁₋₁₀ hydrocarbyl, preferably methyl, ethyl,n-propyl, i-propyl, t-butyl, phenyl, 2,6-dimethylphenyl, benzyl, ortolyl. In addition, two or more Rd or R^(e) groups, or mixtures of Rdand Re groups may together form a polyvalent derivative of a hydrocarbylgroup, such as, 1,4-butylene, 1,5-pentylene, or a multicyclic, fusedring, polyvalent hydrocarbyl- or heterohydrocarbyl-group, such asnaphthalene-1,8-diyl.

Preferred examples of the foregoing polyvalent Lewis base complexesinclude:

wherein R^(d′) each occurrence is independently selected from the groupconsisting of hydrogen and C₁₋₅₀ hydrocarbyl groups optionallycontaining one or more heteroatoms, or inertly substituted derivativethereof, or further optionally, two adjacent R^(d′) groups may togetherform a divalent bridging group;

d′ is 4;

M^(b′) is a group 4 metal, preferably titanium or hafnium or a Group 10metal, preferably Ni or Pd;

L^(b′) is a monovalent ligand of up to 50 atoms not counting hydrogen,preferably halide or hydrocarbyl, or two L^(b′) groups together are adivalent or neutral ligand group, preferably a C₂₋₅₀ hydrocarbylene,hydrocarbadiyl or diene group.

The polyvalent Lewis base complexes for use in the present inventionespecially include Group 4 metal derivatives, especially hafniumderivatives of hydrocarbylamine substituted heteroaryl compoundscorresponding to the formula:

wherein:

R¹¹ is selected from alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl,aryl, and inertly substituted derivatives thereof containing from 1 to30 atoms not counting hydrogen or a divalent derivative thereof;

T¹ is a divalent bridging group of from 1 to 41 atoms other thanhydrogen, preferably 1 to 20 atoms other than hydrogen, and mostpreferably a mono- or di-C₁₋₂₀ hydrocarbyl substituted methylene orsilane group; and

R¹² is a C₅₋₂₀ heteroaryl group containing Lewis base functionality,especially a pyridin-2-yl- or substituted pyridin-2-yl group or adivalent derivative thereof;

M¹ is a Group 4 metal, preferably hafnium;

X¹ is an anionic, neutral or dianionic ligand group;

x′ is a number from 0 to 5 indicating the number of such X¹ groups; and

bonds, optional bonds and electron donative interactions are representedby lines, dotted lines and arrows respectively.

Preferred complexes are those wherein ligand formation results fromhydrogen elimination from the amine group and optionally from the lossof one or more additional groups, especially from R¹². In addition,electron donation from the Lewis base functionality, preferably anelectron pair, provides additional stability to the metal center.Preferred metal complexes correspond to the formula:

wherein

M¹, X¹, x′, R¹¹ and T¹ are as previously defined,

R¹³, R¹⁴, R¹⁵ and R¹⁶ are hydrogen, halo, or an alkyl, cycloalkyl,heteroalkyl, heterocycloalkyl, aryl, or silyl group of up to 20 atomsnot counting hydrogen, or adjacent R¹³, R¹⁴, R¹⁵ or R¹⁶ groups may bejoined together thereby forming fused ring derivatives, and

bonds, optional bonds and electron pair donative interactions arerepresented by lines, dotted lines and arrows respectively.

More preferred examples of the foregoing metal complexes correspond tothe formula:

wherein

M¹, X¹, and x′ are as previously defined,

R¹³, R¹⁴, R¹⁵ and R¹⁶ are as previously defined, preferably R¹³, R¹⁴,and R¹⁵ are hydrogen, or C₁₋₄ alkyl, and R¹⁶ is C₆₋₂₀ aryl, mostpreferably naphthalenyl;

R^(a) independently each occurrence is C₁₋₄ alkyl, and a is 1-5, mostpreferably R^(a) in two ortho-positions to the nitrogen is isopropyl ort-butyl;

R¹⁷ and R¹⁸ independently each occurrence are hydrogen, halogen, or aC₁₋₂₀ alkyl or aryl group, most preferably one of R¹⁷ and R¹⁸ ishydrogen and the other is a C₆₋₂₀ aryl group, especially 2-isopropyl,phenyl or a fused polycyclic aryl group, most preferably an anthracenylgroup, and

bonds, optional bonds and electron pair donative interactions arerepresented by lines, dotted lines and arrows respectively.

Highly preferred metal complexes for use herein correspond to theformula:

wherein X¹ each occurrence is halide, N,N-dimethylamido, or C₁₋₄ alkyl,and preferably each occurrence X¹ is methyl;

R^(f) independently each occurrence is hydrogen, halogen, C₁₋₂₀ alkyl,or C₆₋₂₀ aryl, or two adjacent R^(f) groups are joined together therebyforming a ring, and f is 1-5; and

R^(c) independently each occurrence is hydrogen, halogen, C₁₋₂₀ alkyl,or C₆₋₂₀ aryl, or two adjacent R^(e) groups are joined together therebyforming a ring, and c is 1-5.

Most highly preferred examples of metal complexes for use according tothe present invention are complexes of the following formulas:

wherein R^(x) is C₁₋₄ alkyl or cycloalkyl, preferably methyl, isopropyl,t-butyl or cyclohexyl; and

X¹ each occurrence is halide, N,N-dimethylamido, or C₁₋₄ alkyl,preferably methyl.

Examples of metal complexes usefully employed according to the presentinvention include:

-   [N-(2,6-di(1-methylethyl)phenyl)amido)(o-tolyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dimethyl;-   [N-(2,6-di(1-methylethyl)phenyl)amido)(o-tolyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    di(N,N-dimethylamido);-   [N-(2,6-di(1-methylethyl)phenyl)amido)(o-tolyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dichloride;-   [N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dimethyl;-   [N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    di(N,N-dimethylamido);-   [N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dichloride;-   [N-(2,6-di(1-methylethyl)phenyl)amido)(phenanthren-5-yl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dimethyl;-   [N-(2,6-di(1-methylethyl)phenyl)amido)(phenanthren-5-yl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    di(N,N-dimethylamido); and-   [N-(2,6-di(1-methylethyl)phenyl)amido)(phenanthren-5-yl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafnium    dichloride.

Under the reaction conditions used to prepare the metal complexes usedin the present invention, the hydrogen of the 2-position of theα-naphthalene group substituted at the 6-position of the pyridin-2-ylgroup is subject to elimination, thereby uniquely forming metalcomplexes wherein the metal is covalently bonded to both the resultingamide group and to the 2-position of the α-naphthalenyl group, as wellas stabilized by coordination to the pyridinyl nitrogen atom through theelectron pair of the nitrogen atom.

Additional suitable metal complexes of polyvalent Lewis bases for useherein include compounds corresponding to the formula:

where:

R²⁰ is an aromatic or inertly substituted aromatic group containing from5 to 20 atoms not counting hydrogen, or a polyvalent derivative thereof;

T³ is a hydrocarbylene or silane group having from 1 to 20 atoms notcounting hydrogen, or an inertly substituted derivative thereof;

M³ is a Group 4 metal, preferably zirconium or hafnium;

G is an anionic, neutral or dianionic ligand group; preferably a halide,hydrocarbyl or dihydrocarbylamide group having up to 20 atoms notcounting hydrogen;

g is a number from 1 to 5 indicating the number of such G groups; and

bonds and electron donative interactions are represented by lines andarrows respectively.

Preferably, such complexes correspond to the formula:

wherein:

T³ is a divalent bridging group of from 2 to 20 atoms not countinghydrogen, preferably a substituted or unsubstituted, C₃₋₆ alkylenegroup; and

Ar² independently each occurrence is an arylene or an alkyl- oraryl-substituted arylene group of from 6 to 20 atoms not countinghydrogen;

M³ is a Group 4 metal, preferably hafnium or zirconium;

G independently each occurrence is an anionic, neutral or dianionicligand group;

g is a number from 1 to 5 indicating the number of such X groups; and

electron donative interactions are represented by arrows.

Preferred examples of metal complexes of foregoing formula include thefollowing compounds:

where M³ is Hf or Zr;

Ar⁴ is C₆₋₂₀ aryl or inertly substituted derivatives thereof, especially3,5-di(isopropyl)phenyl, 3,5-di(isobutyl)phenyl,dibenzo-1H-pyrrole-1-yl, or anthracen-5-yl, and

T⁴ independently each occurrence comprises a C₃₋₆ alkylene group, a C₃₋₆cycloalkylene group, or an inertly substituted derivative thereof;

R²¹ independently each occurrence is hydrogen, halo, hydrocarbyl,trihydrocarbylsilyl, or trihydrocarbylsilylhydrocarbyl of up to 50 atomsnot counting hydrogen; and

G, independently each occurrence is halo or a hydrocarbyl ortrihydrocarbylsilyl group of up to 20 atoms not counting hydrogen, or 2G groups together are a divalent derivative of the foregoing hydrocarbylor trihydrocarbylsilyl groups.

Especially preferred are compounds of the formula:

wherein Ar⁴ is 3,5-di(isopropyl)phenyl, 3,5-di(isobutyl)phenyl,dibenzo-1H-pyrrole-1-yl, or anthracen-5-yl,

R²¹ is hydrogen, halo, or C₁₋₄ alkyl, especially methyl

T⁴ is propan-1,3-diyl or butan-1,4-diyl, and

G is chloro, methyl or benzyl.

A most highly preferred metal complex of the foregoing formula is:

The foregoing polyvalent Lewis base complexes are conveniently preparedby standard metallation and ligand exchange procedures involving asource of the Group 4 metal and the neutral polyfunctional ligandsource. In addition, the complexes may also be prepared by means of anamide elimination and hydrocarbylation process starting from thecorresponding Group 4 metal tetraamide and a hydrocarbylating agent,such as trimethylaluminum. Other techniques may be used as well. Thesecomplexes are known from the disclosures of, among others, U.S. Pat.Nos. 6,320,005, 6,103,657, WO 02/38628, WO 03/40195, and US04/0220050.

Catalysts having high comonomer incorporation properties are also knownto reincorporate in situ prepared long chain olefins resultingincidentally during the polymerization through β-hydride elimination andchain termination of growing polymer, or other process. Theconcentration of such long chain olefins is particularly enhanced by useof continuous solution polymerization conditions at high conversions,especially ethylene conversions of 95 percent or greater, morepreferably at ethylene conversions of 97 percent or greater. Under suchconditions a small but detectable quantity of olefin terminated polymermay be reincorporated into a growing polymer chain, resulting in theformation of long chain branches, that is, branches of a carbon lengthgreater than would result from other deliberately added comonomer.Moreover, such chains reflect the presence of other comonomers presentin the reaction mixture. That is, the chains may include short chain orlong chain branching as well, depending on the comonomer composition ofthe reaction mixture.

Additional suitable metal compounds for use herein include Group 4-10metal derivatives corresponding to the formula:

wherein

-   -   M² is a metal of Groups 4-10 of the Periodic Table of the        elements, preferably Group 4 metals, Ni(II) or Pd(II), most        preferably zirconium;    -   T² is a nitrogen, oxygen or phosphorus containing group;    -   X² is halo, hydrocarbyl, or hydrocarbyloxy;    -   t is one or two;    -   x″ is a number selected to provide charge balance;    -   and T² and N are linked by a bridging ligand.

Such catalysts have been previously disclosed in J. Am. Chem. Soc., 118,267-268 (1996), J. Am. Chem. Soc., 117, 6414-6415 (1995), andOrganometallics, 16, 1514-1516, (1997), among other disclosures.

Preferred examples of the foregoing metal complexes are aromatic diimineor aromatic dioxyimine complexes of Group 4 metals, especiallyzirconium, corresponding to the formula:

wherein;

M², X² and T² are as previously defined;

R^(d) independently each occurrence is hydrogen, halogen, or R^(e); and

R^(e) independently each occurrence is C₁₋₂₀ hydrocarbyl or aheteroatom-, especially a F, N, S or P-substituted derivative thereof,more preferably C₁₋₁₀ hydrocarbyl or a F or N substituted derivativethereof, most preferably alkyl, dialkylaminoalkyl, pyrrolyl,piperidenyl, perfluorophenyl, cycloalkyl, (poly)alkylaryl, or aralkyl.

Most preferred examples of the foregoing metal complexes are aromaticdioxyimine complexes of zirconium, corresponding to the formula:

wherein;

X² is as previously defined, preferably C₁₋₁₀ hydrocarbyl, mostpreferably methyl or benzyl; and

R^(e′) is methyl, isopropyl, t-butyl, cyclopentyl, cyclohexyl,2-methylcyclohexyl, 2,4-dimethylcyclohexyl, 2-pyrrolyl,N-methyl-2-pyrrolyl, 2-piperidenyl, N-methyl-2-piperidenyl, benzyl,o-tolyl, 2,6-dimethylphenyl, perfluorophenyl, 2,6-di(isopropyl)phenyl,or 2,4,6-trimethylphenyl.

The foregoing complexes also include certain phosphinimine complexes aredisclosed in EP-A-890581. These complexes correspond to the formula:[(R^(f))₃—P═N]_(f)M(K²)(R^(f))_(3-f), wherein:

R^(f) is a monovalent ligand or two R^(f) groups together are a divalentligand, preferably R^(f) is hydrogen or C₁₋₄ alkyl;

M is a Group 4 metal,

K² is a group containing delocalized π-electrons through which K² isbound to M, said K² group containing up to 50 atoms not countinghydrogen atoms, and

f is 1 or 2.

Cocatalysts

Each of the metal complexes (also interchangeably referred to herein asprocatalysts) may be activated to form the active catalyst compositionby combination with a cocatalyst, preferably a cation formingcocatalyst, a strong Lewis acid, or a combination thereof. In apreferred embodiment, the shuttling agent is employed both for purposesof chain transfer and as the optional cocatalyst component of thecatalyst composition.

The metal complexes desirably are rendered catalytically active bycombination with a cation forming cocatalyst, such as those previouslyknown in the art for use with Group 4 metal olefin polymerizationcomplexes. Suitable cation forming cocatalysts for use herein includeneutral Lewis acids, such as C₁₋₃₀ hydrocarbyl substituted Group 13compounds, especially tri(hydrocarbyl)aluminum- or tri(hydrocarbyl)boroncompounds and halogenated (including perhalogenated) derivativesthereof, having from 1 to 10 carbons in each hydrocarbyl or halogenatedhydrocarbyl group, more especially perfluorinated tri(aryl)boroncompounds, and most especially tris(pentafluoro-phenyl)borane;nonpolymeric, compatible, noncoordinating, ion forming compounds(including the use of such compounds under oxidizing conditions),especially the use of ammonium-, phosphonium-, oxonium-, carbonium-,silylium- or sulfonium-salts of compatible, noncoordinating anions, orferrocenium-, lead- or silver salts of compatible, noncoordinatinganions; and combinations of the foregoing cation forming cocatalysts andtechniques. The foregoing activating cocatalysts and activatingtechniques have been previously taught with respect to different metalcomplexes for olefin polymerizations in the following references:EP-A-277,003, U.S. Pat. No. 5,153,157, U.S. Pat. No. 5,064,802, U.S.Pat. No. 5,321,106, U.S. Pat. No. 5,721,185, U.S. Pat. No. 5,350,723,U.S. Pat. No. 5,425,872, U.S. Pat. No. 5,625,087, U.S. Pat. No.5,883,204, U.S. Pat. No. 5,919,983, U.S. Pat. No. 5,783,512, WO99/15534, and WO99/42467.

Combinations of neutral Lewis acids, especially the combination of atrialkyl aluminum compound having from 1 to 4 carbons in each alkylgroup and a halogenated tri(hydrocarbyl)boron compound having from 1 to20 carbons in each hydrocarbyl group, especiallytris(pentafluorophenyl)borane, further combinations of such neutralLewis acid mixtures with a polymeric or oligomeric alumoxane, andcombinations of a single neutral Lewis acid, especiallytris(pentafluorophenyl)borane with a polymeric or oligomeric alumoxanemay be used as activating cocatalysts. Preferred molar ratios of metalcomplex:tris(pentafluorophenyl-borane:alumoxane are from 1:1:1 to1:5:20, more preferably from 1:1:1.5 to 1:5:10.

Suitable ion forming compounds useful as cocatalysts in one embodimentof the present invention comprise a cation which is a Bronsted acidcapable of donating a proton, and a compatible, noncoordinating anion,A⁻. As used herein, the term “noncoordinating” means an anion orsubstance which either does not coordinate to the Group 4 metalcontaining precursor complex and the catalytic derivative derived therefrom, or which is only weakly coordinated to such complexes therebyremaining sufficiently labile to be displaced by a neutral Lewis base. Anoncoordinating anion specifically refers to an anion which whenfunctioning as a charge balancing anion in a cationic metal complex doesnot transfer an anionic substituent or fragment thereof to said cationthereby forming neutral complexes. “Compatible anions” are anions whichare not degraded to neutrality when the initially formed complexdecomposes and are noninterfering with desired subsequent polymerizationor other uses of the complex.

Preferred anions are those containing a single coordination complexcomprising a charge-bearing metal or metalloid core which anion iscapable of balancing the charge of the active catalyst species (themetal cation) which may be formed when the two components are combined.Also, said anion should be sufficiently labile to be displaced byolefinic, diolefinic and acetylenically unsaturated compounds or otherneutral Lewis bases such as ethers or nitrites. Suitable metals include,but are not limited to, aluminum, gold and platinum. Suitable metalloidsinclude, but are not limited to, boron, phosphorus, and silicon.Compounds containing anions which comprise coordination complexescontaining a single metal or metalloid atom are, of course, well knownand many, particularly such compounds containing a single boron atom inthe anion portion, are available commercially.

Preferably such cocatalysts may be represented by the following generalformula:(L*−H)_(g) ⁺(A)^(g−)wherein:

L* is a neutral Lewis base;

(L*−H)⁺ is a conjugate Bronsted acid of L*;

A^(g−) is a noncoordinating, compatible anion having a charge of g−, and

g is an integer from 1 to 3.

More preferably A^(g−) corresponds to the formula: [M′Q₄]⁻;

wherein:

M′ is boron or aluminum in the +3 formal oxidation state; and

Q independently each occurrence is selected from hydride, dialkylamido,halide, hydrocarbyl, hydrocarbyloxide, halosubstituted-hydrocarbyl,halosubstituted hydrocarbyloxy, and halo-substituted silylhydrocarbylradicals (including perhalogenated hydrocarbyl-perhalogenatedhydrocarbyloxy- and perhalogenated silylhydrocarbyl radicals), said Qhaving up to 20 carbons with the proviso that in not more than oneoccurrence is Q halide. Examples of suitable hydrocarbyloxide Q groupsare disclosed in U.S. Pat. No. 5,296,433.

In a more preferred embodiment, d is one, that is, the counter ion has asingle negative charge and is A⁻. Activating cocatalysts comprisingboron which are particularly useful in the preparation of catalysts ofthis invention may be represented by the following general formula:(L*−H)⁺(BQ₄)⁻;wherein:

L* is as previously defined;

B is boron in a formal oxidation state of 3; and

Q is a hydrocarbyl-, hydrocarbyloxy-, fluorinated hydrocarbyl-,fluorinated hydrocarbyloxy-, or fluorinated silylhydrocarbyl-group of upto 20 nonhydrogen atoms, with the proviso that in not more than oneoccasion is Q hydrocarbyl.

Preferred Lewis base salts are ammonium salts, more preferablytrialkylammonium salts containing one or more C₁₂₋₄₀ alkyl groups. Mostpreferably, Q is each occurrence a fluorinated aryl group, especially, apentafluorophenyl group.

Illustrative, but not limiting, examples of boron compounds which may beused as an activating cocatalyst in the preparation of the improvedcatalysts of this invention are tri-substituted ammonium salts such as:

-   trimethylammonium tetrakis(pentafluorophenyl) borate,-   triethylammonium tetrakis(pentafluorophenyl) borate,-   tripropylammonium tetrakis(pentafluorophenyl) borate,-   tri(n-butyl)ammonium tetrakis(pentafluorophenyl) borate,-   tri(sec-butyl)ammonium tetrakis(pentafluorophenyl) borate,-   N,N-dimethylanilinium tetrakis(pentafluorophenyl) borate,-   N,N-dimethylanilinium n-butyltris(pentafluorophenyl) borate,-   N,N-dimethylanilinium benzyltris(pentafluorophenyl) borate,-   N,N-dimethylanilinium    tetrakis(4-(t-butyldimethylsilyl)-2,3,5,6-tetrafluorophenyl) borate,-   N,N-dimethylanilinium    tetrakis(4-(triisopropylsilyl)-2,3,5,6-tetrafluorophenyl) borate,-   N,N-dimethylanilinium pentafluorophenoxytris(pentafluorophenyl)    borate,-   N,N-diethylanilinium tetrakis(pentafluorophenyl) borate,-   N,N-dimethyl-2,4,6-trimethylanilinium tetrakis(pentafluorophenyl)    borate,-   dimethyloctadecylammonium tetrakis(pentafluorophenyl) borate,-   methyldioctadecylammonium tetrakis(pentafluorophenyl) borate,    dialkyl ammonium salts such as:-   di-(i-propyl)ammonium tetrakis(pentafluorophenyl) borate,-   methyloctadecylammonium tetrakis(pentafluorophenyl) borate,-   methyloctadodecylammonium tetrakis(pentafluorophenyl) borate, and-   dioctadecylammonium tetrakis(pentafluorophenyl) borate;    tri-substituted phosphonium salts such as:-   triphenylphosphonium tetrakis(pentafluorophenyl) borate,-   methyldioctadecylphosphonium tetrakis(pentafluorophenyl) borate, and-   tri(2,6-dimethylphenyl)phosphonium tetrakis(pentafluorophenyl)    borate;    di-substituted oxonium salts such as:-   diphenyloxonium tetrakis(pentafluorophenyl) borate,-   di(o-tolyl)oxonium tetrakis(pentafluorophenyl) borate, and-   di(octadecyl)oxonium tetrakis(pentafluorophenyl) borate;    di-substituted sulfonium salts such as:-   di(o-tolyl)sulfonium tetrakis(pentafluorophenyl) borate, and-   methylcotadecylsulfonium tetrakis(pentafluorophenyl) borate.

Preferred (L*−H)⁺ cations are methyldioctadecylammonium cations,dimethyloctadecylammonium cations, and ammonium cations derived frommixtures of trialkyl amines containing one or 2 C₁₄₋₁₈ alkyl groups.

Another suitable ion forming, activating cocatalyst comprises a salt ofa cationic oxidizing agent and a noncoordinating, compatible anionrepresented by the formula:(Ox^(h+))_(g)(A^(g−))_(h),wherein:

Ox^(h+) is a cationic oxidizing agent having a charge of h+;

h is an integer from 1 to 3; and

A^(g−) and g are as previously defined.

Examples of cationic oxidizing agents include: ferrocenium,hydrocarbyl-substituted ferrocenium, Ag^(+′) or Pb⁺². Preferredembodiments of A^(g−) are those anions previously defined with respectto the Bronsted acid containing activating cocatalysts, especiallytetrakis(pentafluorophenyl)borate.

Another suitable ion forming, activating cocatalyst comprises a compoundwhich is a salt of a carbenium ion and a noncoordinating, compatibleanion represented by the formula:[C]⁺A⁻wherein:

[C]⁺ is a C₁₋₂₀ carbenium ion; and

A⁻ is a noncoordinating, compatible anion having a charge of −1. Apreferred carbenium ion is the trityl cation, that istriphenylmethylium.

A further suitable ion forming, activating cocatalyst comprises acompound which is a salt of a silylium ion and a noncoordinating,compatible anion represented by the formula:(Q¹ ₃Si)⁺A⁻wherein:

Q¹ is C₁₋₁₀ hydrocarbyl, and A⁻ is as previously defined.

Preferred silylium salt activating cocatalysts are trimethylsilyliumtetrakispentafluorophenylborate, triethylsilyliumtetrakispentafluorophenylborate and ether substituted adducts thereof.Silylium salts have been previously generically disclosed in J. Chem.Soc. Chem. Comm., 1993, 383-384, as well as Lambert, J. B., et al.,Organometallics, 1994, 13, 2430-2443. The use of the above silyliumsalts as activating cocatalysts for addition polymerization catalysts isdisclosed in U.S. Pat. No. 5,625,087.

Certain complexes of alcohols, mercaptans, silanols, and oximes withtris(pentafluorophenyl)borane are also effective catalyst activators andmay be used according to the present invention. Such cocatalysts aredisclosed in U.S. Pat. No. 5,296,433.

Suitable activating cocatalysts for use herein also include polymeric oroligomeric alumoxanes, especially methylalumoxane (MAO), triisobutylaluminum modified methylalumoxane (MMAO), or isobutylalumoxane; Lewisacid modified alumoxanes, especially perhalogenatedtri(hydrocarbyl)aluminum- or perhalogenated tri(hydrocarbyl)boronmodified alumoxanes, having from 1 to 10 carbons in each hydrocarbyl orhalogenated hydrocarbyl group, and most especiallytris(pentafluorophenyl)borane modified alumoxanes. Such cocatalysts arepreviously disclosed in U.S. Pat. Nos. 6,214,760, 6,160,146, 6,140,521,and 6,696,379.

A class of cocatalysts comprising non-coordinating anions genericallyreferred to as expanded anions, further disclosed in U.S. Pat. No.6,395,671, may be suitably employed to activate the metal complexes ofthe present invention for olefin polymerization. Generally, thesecocatalysts (illustrated by those having imidazolide, substitutedimidazolide, imidazolinide, substituted imidazolinide, benzimidazolide,or substituted benzimidazolide anions) may be depicted as follows:

wherein:

A*⁺ is a cation, especially a proton containing cation, and preferablyis a trihydrocarbyl ammonium cation containing one or two C₁₀₋₄₀ alkylgroups, especially a methyldi(C₁₄₋₂₀ alkyl)ammonium cation,

Q³, independently each occurrence, is hydrogen or a halo, hydrocarbyl,halocarbyl, halohydrocarbyl, silylhydrocarbyl, or silyl, (includingmono-, di- and tri(hydrocarbyl)silyl) group of up to 30 atoms notcounting hydrogen, preferably C₁₋₂₀ alkyl, and

Q² is tris(pentafluorophenyl)borane or tris(pentafluorophenyl)alumane).

Examples of these catalyst activators includetrihydrocarbylammonium-salts, especially, methyldi(C₁₄₋₂₀alkyl)ammonium-salts of:

-   bis(tris(pentafluorophenyl)borane)imidazolide,-   bis(tris(pentafluorophenyl)borane)-2-undecylimidazolide,-   bis(tris(pentafluorophenyl)borane)-2-heptadecylimidazolide,-   bis(tris(pentafluorophenyl)borane)-4,5-bis(undecyl)imidazolide,-   bis(tris(pentafluorophenyl)borane)-4,5-bis(heptadecyl)imidazolide,-   bis(tris(pentafluorophenyl)borane)imidazolinide,-   bis(tris(pentafluorophenyl)borane)-2-undecylimidazolinide,-   bis(tris(pentafluorophenyl)borane)-2-heptadecylimidazolinide,    bis(tris(pentafluorophenyl)borane)-4,5-bis(undecyl)imidazolinide,-   bis(tris(pentafluorophenyl)borane)-4,5-bis(heptadecyl)imidazolinide,-   bis(tris(pentafluorophenyl)borane)-5,6-dimethylbenzimidazolide,-   bis(tris(pentafluorophenyl)borane)-5,6-bis(undecyl)benzimidazolide,-   bis(tris(pentafluorophenyl)alumane)imidazolide,-   bis(tris(pentafluorophenyl)alumane)-2-undecylimidazolide,-   bis(tris(pentafluorophenyl)alumane)-2-heptadecylimidazolide,-   bis(tris(pentafluorophenyl)alumane)-4,5-bis(undecyl)imidazolide,-   bis(tris(pentafluorophenyl)alumane)-4,5-bis(heptadecyl)imidazolide,-   bis(tris(pentafluorophenyl)alumane)imidazolinide,-   bis(tris(pentafluorophenyl)alumane)-2-undecylimidazolinide,-   bis(tris(pentafluorophenyl)alumane)-2-heptadecylimidazolinide,-   bis(tris(pentafluorophenyl)alumane)-4,5-bis(undecyl)imidazolinide,-   bis(tris(pentafluorophenyl)alumane)-4,5-bis(heptadecyl)imidazolinide,-   bis(tris(pentafluorophenyl)alumane)-5,6-dimethylbenzimidazolide, and-   bis(tris(pentafluorophenyl)alumane)-5,6-bis(undecyl)benzimidazolide.

Other activators include those described in PCT publication WO 98/07515such as tris(2,2′,2″-nonafluorobiphenyl)fluoroaluminate. Combinations ofactivators are also contemplated by the invention, for example,alumoxanes and ionizing activators in combinations, see for example,EP-A-0 573120, PCT publications WO 94/07928 and WO 95/14044 and U.S.Pat. Nos. 5,153,157 and 5,453,410. WO 98/09996 describes activatingcatalyst compounds with perchlorates, periodates and iodates, includingtheir hydrates. WO 99/18135 describes the use of organoboroaluminumactivators. WO 03/10171 discloses catalyst activators that are adductsof Bronsted acids with Lewis acids. Other activators or methods foractivating a catalyst compound are described in for example, U.S. Pat.Nos. 5,849,852, 5,859,653, 5,869,723, EP-A-615981, and PCT publicationWO 98/32775. All of the foregoing catalyst activators as well as anyother know activator for transition metal complex catalysts may beemployed alone or in combination according to the present invention,however, for best results alumoxane containing cocatalysts are avoided.

The molar ratio of catalyst/cocatalyst employed preferably ranges from1:10,000 to 100:1, more preferably from 1:5000 to 10:1, most preferablyfrom 1:1000 to 1:1. Alumoxane, when used by itself as an activatingcocatalyst, is employed in large quantity, generally at least 100 timesthe quantity of metal complex on a molar basis.Tris(pentafluorophenyl)borane, where used as an activating cocatalyst isemployed in a molar ratio to the metal complex of from 0.5:1 to 10:1,more preferably from 1:1 to 6:1 most preferably from 1:1 to 5:1. Theremaining activating cocatalysts are generally employed in approximatelyequimolar quantity with the metal complex.

The process of the invention employing a catalyst one or morecocatalysts and chain shuttling agent may be further elucidated byreference to FIG. 1, where there is illustrated activated catalyst, 10,which under polymerization conditions forms a polymer chain, 13,attached to the active catalyst site, 12. A chain shuttling agent, 14,attaches to a polymer chain produced by an active catalyst site, andsubsequently causes insertion of the chain segment into the activecatalyst site to prepare a second generation polymer 16, which undergoesadditional chain growth under polymerization conditions different fromthose during which the initial polymer segment is formed thereby forminga pseudo-block copolymer, 18 attached to the active catalyst. Therespective polymer segments formed in the process are distinguishablebecause the polymerization conditions in existence at the time offormation of the respective blocks or segments are different and thechain shuttling agent is able to prolong the polymer life time (that isthe time during which further polymer growth may occur) until two ormore different polymerization environments are experienced. There may berepeated exchanges between the active catalyst and the shuttling agentoccurring under various differing polymerization conditions. Theresulting copolymer comprises blocks or segments of differing propertieswhenever exchange to an area of the reactor operating under differingreaction conditions occurs. By cycling the foregoing exchange severaltimes, preferably many times, the comonomer distribution or otherdistinguishing property in the resulting blocks becomes more random andapproaches a most probable distribution.

The growing polymer chains may be recovered while attached to a chainshuttling agent and functionalized if desired. Alternatively, theresulting polymer may be recovered by scission from the active catalystsite or from the shuttling agent, through use of a proton source orother killing agent.

During the polymerization, the reaction mixture is contacted with theactivated catalyst composition according to any suitable polymerizationconditions. The process is desirably characterized by use of elevatedtemperatures and pressures. Hydrogen may be employed as a separate chaintransfer agent for molecular weight control according to knowntechniques if desired. All of the foregoing process conditions may bevaried continuously or discontinuously over separate regions of thereactor or among different reactors according to the invention. As inother similar polymerizations, it is highly desirable that the monomersand solvents employed be of sufficiently high purity that catalystdeactivation does not occur. Any suitable technique for monomerpurification such as devolatilization at reduced pressure, contactingwith molecular sieves or high surface area alumina, or a combination ofthe foregoing processes may be employed.

Supports may be employed in the present invention, especially in slurryor gas-phase polymerizations. Suitable supports include solid,particulated, high surface area, metal oxides, metalloid oxides, ormixtures thereof (interchangeably referred to herein as an inorganicoxide). Examples include: talc, silica, alumina, magnesia, titania,zirconia, Sn₂O₃, aluminosilicates, borosilicates, clays, and mixturesthereof. Suitable supports preferably have a surface area as determinedby nitrogen porosimetry using the B.E.T. method from 10 to 1000 m²/g,and preferably from 100 to 600 m²/g. The average particle size typicallyis from 0.1 to 500 μm, preferably from 1 to 200 μm, more preferably 10to 100 μm.

In one embodiment of the invention the present catalyst composition andoptional support may be spray dried or otherwise recovered in solid,particulated form to provide a composition that is readily transportedand handled. Suitable methods for spray drying a liquid containingslurry are well known in the art and usefully employed herein. Preferredtechniques for spray drying catalyst compositions for use herein aredescribed in U.S. Pat. Nos. 5,648,310 and 5,672,669.

The polymerization is desirably carried out as a continuouspolymerization, preferably a continuous, solution polymerization, inwhich catalyst components, shuttling agent(s), monomers, and optionallysolvent, adjuvants, scavengers, and polymerization aids are continuouslysupplied to the reaction zone and polymer product continuously removedthere from. Within the scope of the terms “continuous” and“continuously” as used in this context are those processes in whichthere are intermittent additions of reactants and removal of products atsmall regular or irregular intervals, so that, over time, the overallprocess is substantially continuous. Moreover, as previously explained,a monomer gradient, temperature gradient, pressure gradient, or otherdifference in polymerization conditions is maintained between at leasttwo regions of the reactor undergoing polymerization or in differingreactors connected in a closed loop or cycle, so that polymer segmentsof differing composition such as comonomer content, crystallinity,density, tacticity, regio-regularity, or other chemical or physicaldifference are formed at different times during formation of the growingpolymer chain.

The process can be operated in a high pressure, solution, slurry, or gasphase polymerization process. For a solution polymerization process itis desirable to employ homogeneous dispersions of the catalystcomponents in a liquid diluent in which the polymer is soluble under thepolymerization conditions employed. One such process utilizing anextremely fine silica or similar dispersing agent to produce such ahomogeneous catalyst dispersion where either the metal complex or thecocatalyst is only poorly soluble is disclosed in U.S. Pat. No.5,783,512. A high pressure process is usually carried out attemperatures from 100° C. to 400° C. and at pressures above 500 bar (50MPa). A slurry process typically uses an inert hydrocarbon diluent andtemperatures of from 0° C. up to a temperature just below thetemperature at which the resulting polymer becomes substantially solublein the inert polymerization medium. Preferred temperatures in a slurrypolymerization are from 30° C., preferably from 60° C. up to 115° C.,preferably up to 100° C. Pressures typically range from atmospheric (100kPa) to 500 psi (3.4 MPa).

In all of the foregoing processes, continuous or substantiallycontinuous polymerization conditions are preferably employed. The use ofsuch polymerization conditions, especially continuous, solutionpolymerization processes, allows the use of elevated reactortemperatures which results in the economical production of pseudo-blockcopolymers in high yields and efficiencies. Both homogeneous andplug-flow type reaction conditions may be employed with the proviso thata gradient of at least one process condition with respect to polymerchain formation over time is achieved. Desirably, at least some polymeris present at the point of catalyst or monomer addition. This may beaccomplished in one embodiment by use of varying quantities of recycle(including no recycle). A highly preferred reactor for use herein is aloop or tubular reactor. Also suitable is the use of multiple reactors,especially multiple continuous stirred or back-mixed reactors (CSTR),desirably connected in series, or multiple zones in a reactor.

The metal complex may be prepared as a homogeneous composition byaddition of the requisite metal complex or multiple complexes to asolvent in which the polymerization will be conducted or in a diluentcompatible with the ultimate reaction mixture. The desired cocatalyst oractivator and the shuttling agent may be combined with the catalystcomposition either prior to, simultaneously with, or after combinationwith the monomers to be polymerized and any additional reaction diluent.

At all times, the individual ingredients as well as any active catalystcomposition must be protected from oxygen, moisture and other catalystpoisons. Therefore, the catalyst components, shuttling agent andactivated catalysts must be prepared and stored in an oxygen andmoisture free atmosphere, preferably under a dry, inert gas such asnitrogen.

Without limiting in any way the scope of the invention, one means forcarrying out such a polymerization process is as follows. In one or moreloop reactors operating under solution polymerization conditions, themonomers to be polymerized are introduced continuously together with anysolvent or diluent at one part of the reactor. The reactor contains aliquid phase composed substantially of monomers together with anysolvent or diluent and dissolved polymer. Preferred solvents includeC₄₋₁₀ hydrocarbons or mixtures thereof, especially alkanes such ashexane or mixtures of alkanes, as well as one or more of the monomersemployed in the polymerization. Examples of suitable loop reactors and avariety of suitable operating conditions for use therewith, includingthe use of multiple loop reactors, operating in series, are found inU.S. Pat. Nos. 5,977,251, 6,319,989 and 6,683,149.

Catalyst along with cocatalyst and chain shuttling agent arecontinuously or intermittently introduced in the reactor liquid phase orany recycled portion thereof at a minimum of one location. The reactortemperature and pressure may be controlled by adjusting thesolvent/monomer ratio, the catalyst addition rate, as well as by coolingor heating coils, jackets or both. The polymerization rate is controlledby the rate of catalyst addition. The ethylene content of the polymerproduct is determined by the ratio of ethylene to comonomer in thereactor, which is controlled by manipulating the respective feed ratesof these components to the reactor. The polymer product molecular weightis controlled, optionally, by controlling other polymerization variablessuch as the temperature, monomer concentration, or by the previouslymentioned chain shuttling agent, as is well known in the art. Between atleast two regions of the reactor, a differential in at least one processcondition is established. Preferably for use in formation of a copolymerof two or more monomers, the difference is a difference in comonomercontent. Upon exiting the reactor, the effluent is contacted with acatalyst kill agent such as water, steam or an alcohol. The polymersolution is optionally heated, and the polymer product is recovered byflashing off gaseous monomers as well as residual solvent or diluent atreduced pressure, and, if necessary, conducting further devolatilizationin equipment such as a devolatilizing extruder. In a continuous processthe mean residence time of the catalyst and polymer in the reactorgenerally is from 5 minutes to 8 hours, and preferably from 10 minutesto 6 hours.

Alternatively, the foregoing polymerization may be carried out in a plugflow reactor with a monomer, catalyst, shuttling agent, temperature orother gradient established between differing regions thereof, optionallyaccompanied by separated addition of catalysts and/or chain shuttlingagent, and operating under adiabatic or non-adiabatic polymerizationconditions.

The catalyst composition may also be prepared and employed as aheterogeneous catalyst by adsorbing the requisite components on an inertinorganic or organic particulated solid, as previously disclosed. In apreferred embodiment, a heterogeneous catalyst is prepared byco-precipitating the metal complex and the reaction product of an inertinorganic compound and an active hydrogen containing activator,especially the reaction product of a tri(C₁₋₄ alkyl) aluminum compoundand an ammonium salt of a hydroxyaryltris(pentafluorophenyl)borate, suchas an ammonium salt of(4-hydroxy-3,5-ditertiarybutylphenyl)tris(pentafluorophenyl)borate. Whenprepared in heterogeneous or supported form, the catalyst compositionmay be employed in a slurry or a gas phase polymerization. As apractical limitation, slurry polymerization takes place in liquiddiluents in which the polymer product is substantially insoluble.Preferably, the diluent for slurry polymerization is one or morehydrocarbons with less than 5 carbon atoms. If desired, saturatedhydrocarbons such as ethane, propane or butane may be used in whole orpart as the diluent. As with a solution polymerization, the α-olefincomonomer or a mixture of different x-olefin monomers may be used inwhole or part as the diluent. Most preferably at least a major part ofthe diluent comprises the α-olefin monomer or monomers to bepolymerized.

Preferably for use in gas phase polymerization processes, the supportmaterial and resulting catalyst has a median particle diameter from 20to 200 μm, more preferably from 30 μm to 150 μm, and most preferablyfrom 50 μm to 100 μm. Preferably for use in slurry polymerizationprocesses, the support has a median particle diameter from 1 μm to 200μm, more preferably from 5 μm to 100 μm, and most preferably from 10 μmto 80 μm.

Suitable gas phase polymerization process for use herein aresubstantially similar to known processes used commercially on a largescale for the manufacture of polypropylene, ethylene/α-olefincopolymers, and other olefin polymers. The gas phase process employedcan be, for example, of the type which employs a mechanically stirredbed or a gas fluidized bed as the polymerization reaction zone.Preferred is the process wherein the polymerization reaction is carriedout in a vertical cylindrical polymerization reactor containing afluidized bed of polymer particles supported or suspended above aperforated plate or fluidization grid, by a flow of fluidization gas.

The gas employed to fluidize the bed comprises the monomer or monomersto be polymerized, and also serves as a heat exchange medium to removethe heat of reaction from the bed. The hot gases emerge from the top ofthe reactor, normally via a tranquilization zone, also known as avelocity reduction zone, having a wider diameter than the fluidized bedand wherein fine particles entrained in the gas stream have anopportunity to gravitate back into the bed. It can also be advantageousto use a cyclone to remove ultra-fine particles from the hot gas stream.The gas is then normally recycled to the bed by means of a blower orcompressor and one or more heat exchangers to strip the gas of the heatof polymerization.

A preferred method of cooling of the bed, in addition to the coolingprovided by the cooled recycle gas, is to feed a volatile liquid to thebed to provide an evaporative cooling effect, often referred to asoperation in the condensing mode. The volatile liquid employed in thiscase can be, for example, a volatile inert liquid, for example, asaturated hydrocarbon having 3 to 8, preferably 4 to 6, carbon atoms. Inthe case that the monomer or comonomer itself is a volatile liquid, orcan be condensed to provide such a liquid, this can suitably be fed tothe bed to provide an evaporative cooling effect. The volatile liquidevaporates in the hot fluidized bed to form gas which mixes with thefluidizing gas. If the volatile liquid is a monomer or comonomer, itwill undergo some polymerization in the bed. The evaporated liquid thenemerges from the reactor as part of the hot recycle gas, and enters thecompression/heat exchange part of the recycle loop. The recycle gas iscooled in the heat exchanger and, if the temperature to which the gas iscooled is below the dew point, liquid will precipitate from the gas.This liquid is desirably recycled continuously to the fluidized bed. Itis possible to recycle the precipitated liquid to the bed as liquiddroplets carried in the recycle gas stream. This type of process isdescribed, for example in EP-89691; U.S. Pat. No. 4,543,399; WO-94/25495and U.S. Pat. No. 5,352,749. A particularly preferred method ofrecycling the liquid to the bed is to separate the liquid from therecycle gas stream and to reinject this liquid directly into the bed,preferably using a method which generates fine droplets of the liquidwithin the bed. This type of process is described in WO-94/28032.

The polymerization reaction occurring in the gas fluidized bed iscatalyzed by the continuous or semi-continuous addition of catalystcomposition according to the invention. The catalyst composition may besubjected to a prepolymerization step, for example, by polymerizing asmall quantity of olefin monomer in a liquid inert diluent, to provide acatalyst composite comprising supported catalyst particles embedded inolefin polymer particles as well.

The polymer is produced directly in the fluidized bed by polymerizationof the monomer or mixture of monomers on the fluidized particles ofcatalyst composition, supported catalyst composition or prepolymerizedcatalyst composition within the bed. Start-up of the polymerizationreaction is achieved using a bed of preformed polymer particles, whichare preferably similar to the desired polymer, and conditioning the bedby drying with inert gas or nitrogen prior to introducing the catalystcomposition, the monomers and any other gases which it is desired tohave in the recycle gas stream, such as a diluent gas, hydrogen chaintransfer agent, or an inert condensable gas when operating in gas phasecondensing mode. The produced polymer is discharged continuously orsemi-continuously from the fluidized bed as desired.

The gas phase processes most suitable for the practice of this inventionare continuous processes which provide for the continuous supply ofreactants to the reaction zone of the reactor and the removal ofproducts from the reaction zone of the reactor, thereby providing asteady-state environment on the macro scale in the reaction zone of thereactor. Products are readily recovered by exposure to reduced pressureand optionally elevated temperatures (devolatilization) according toknown techniques. Typically, the fluidized bed of the gas phase processis operated at temperatures greater than 50° C., preferably from 60° C.to 110° C., more preferably from 70° C. to 110° C.

Suitable gas phase processes which are adaptable for use in the processof this invention are disclosed in U.S. Pat. Nos. 4,588,790; 4,543,399;5,352,749; 5,436,304; 5,405,922; 5,462,999; 5,461,123; 5,453,471;5,032,562; 5,028,670; 5,473,028; 5,106,804; 5,556,238; 5,541,270;5,608,019; and 5,616,661.

As previously mentioned, functionalized derivatives of pseudo-blockcopolymers are also included within the present invention. Examplesinclude metallated polymers wherein the metal is the remnant of thecatalyst or chain shuttling agent employed, as well as furtherderivatives thereof, for example, the reaction product of a metallatedpolymer with an oxygen source and then with water to form a hydroxylterminated polymer. Additional examples include olefin terminatedpolymers formed by β-hydride elimination.

Because a substantial fraction of the polymeric product exiting thereactor is terminated with the chain shuttling agent, furtherfunctionalization is relatively easy. The metallated polymer species canbe utilized in well known chemical reactions such as those suitable forother alkyl-aluminum, alkyl-gallium, alkyl-zinc, or alkyl-Group 1compounds to form amine-, hydroxy-, epoxy-, and other functionalizedterminated polymer products. Examples of suitable reaction techniquesthat are adaptable for use here in are described in Negishi,“Orgaonmetallics in Organic Synthesis”, Vol. 1 and 2, (1980), and otherstandard texts in organometallic and organic synthesis.

Polymer Products

Utilizing the present process, novel polymers, including pseudo-blockcopolymers of one or more olefin monomers, are readily prepared.Preferred polymers comprise in polymerized form at least one monomerselected from the group consisting of ethylene, propylene and4-methyl-1-pentene. Highly desirably, the polymers are interpolymerscomprising in polymerized form ethylene, propylene or 4-methyl-1-penteneand at least one different C₂₋₂₀ α-olefin comonomer, and optionally oneor more additional copolymerizable comonomers. Suitable comonomers areselected from diolefins, cyclic olefins, and cyclic diolefins,halogenated vinyl compounds, and vinylidene aromatic compounds.

The polymers of the invention can have a melt index, 12, from 0.01 to2000 g/10 minutes, preferably from 0.01 to 1000 g/10 minutes, morepreferably from 0.01 to 500 g/10 minutes, and especially from 0.01 to100 g/10 minutes. Desirably, the invented polymers can have molecularweights, M_(w), from 1,000 g/mole to 5,000,000 g/mole, preferably from1000 g/mole to 1,000,000, more preferably from 1000 g/mole to 500,000g/mole, and especially from 1,000 g/mole to 300,000 g/mole. The densityof the invented polymers can be from 0.80 to 0.99 g/cm³ and preferablyfor ethylene containing polymers from 0.85 g/cm³ to 0.97 g/cm³.

The polymers of the invention may be differentiated from conventional,random copolymers, physical blends of polymers, and block copolymersprepared via sequential monomer addition, fluxional catalysts, anionicor cationic living polymerization techniques. The separate regions orblocks within each polymer contain gradual changes in composition(tapering) rather than distinct starting and ending points. In addition,several cycles between extremes of polymer composition, such as multiplegradual changes in comonomer distribution may be present in eachpolymer. For example, the comonomer distribution, tacticity, or otherproperty of segments within the polymer may cycle several times betweena maximum and minimum within the same polymer because the polymerexperienced different process conditions during the course of itsproduction and segments formed under various conditions while attachedto the active catalyst are all present in the polymer. The variousmaxima and minima are characterized by increased crystallinity,tacticity, or other physical property, depending on the processcondition being varied. Preferably, polymer is formed in regions of thereactor wherein monomer/comonomer ratio or comonomer content is varied.Because the polymer products have multiple blocks or segments, but fewor none of the blocks are identical in size or composition, they arereferred to as pseudo-block copolymers. The resulting polymers haveproperties approximating in many respects, those of pure blockcopolymers, and in some aspects exceeding the properties of pure blockcopolymers. In a final distinguishing feature, the blocks or segments ofthe pseudo-block copolymers in one embodiment of the invention may beshown to gradually change in one or more physical properties ormeasurements over sets of adjacent blocks rather than abruptly changebetween blocks. Preferred polymers have at least 4, more preferably atleast 5 segments formed according to the present invention.

Compared to a random copolymer of the same monomers and monomer contentat equivalent crystallinity or modulus, the polymers of the inventionhave one or more distinguishing features, including better (higher) heatresistance as measured by melting point, higher TMA penetrationtemperature, higher high-temperature tensile strength, and/or higherhigh-temperature torsion modulus as determined by dynamic mechanicalanalysis. Compared to a random copolymer comprising the same monomersand monomer content, the inventive polymers have one or more of thefollowing: lower compression set, particularly at elevated temperatures,lower stress relaxation, higher creep resistance, higher tear strength,higher blocking resistance, faster setup due to higher crystallization(solidification) temperature, higher recovery (particularly at elevatedtemperatures), better abrasion resistance, higher retractive force, andbetter oil and filler acceptance.

The polymers desirably comprise distributions in number, block size,and/or composition of polymer blocks, which are Schultz-Flory or mostprobable distributions.

Other highly desirable compositions according to the present inventionare elastomeric interpolymers of ethylene, a C₃₋₂₀ α-olefin, especiallypropylene, and optionally one or more diene monomers. Preferredα-olefins for use in this embodiment of the present invention aredesignated by the formula CH₂═CHR*, where R* is a linear or branchedalkyl group of from 1 to 12 carbon atoms. Examples of suitable α-olefinsinclude, but are not limited to, propylene, isobutylene, 1-butene,1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene. A particularlypreferred α-olefin is propylene. The propylene based polymers aregenerally referred to in the art as EP or EPDM polymers depending onwhether a copolymerized diene is also present. Suitable dienes for usein preparing pseudo-block EPDM type polymers include conjugated ornon-conjugated, straight or branched chain-, cyclic- orpolycyclic-dienes containing from 4 to 20 carbons. Preferred dienesinclude 1,4-pentadiene, 1,4-hexadiene, 5-ethylidene-2-norbornene,dicyclopentadiene, cyclohexadiene, and 5-butylidene-2-norbornene. Aparticularly preferred diene is 5-ethylidene-2-norbornene.

Because the diene containing polymers contain alternating segments orblocks containing greater or lesser quantities of the diene (includingnone) and α-olefin (including none), the total quantity of diene andα-olefin may be reduced without loss of subsequent polymer properties.That is, because the diene and α-olefin monomers are preferentiallyincorporated into one type of block of the polymer rather than uniformlyor randomly throughout the polymer, they are more efficiently utilizedand subsequently the crosslink density of the polymer can be bettercontrolled. Such crosslinkable elastomers and the cured products haveadvantaged properties, including higher tensile strength and betterelastic recovery.

Further preferably, the pseudo-block polymers of the invention have anethylene content from 1 to 99 percent, a diene content from 0 to 10percent, and a styrene and/or C₃₋₈ α-olefin content from 99 to 1percent, based on the total weight of the polymer. Preferred polymersare interpolymers of ethylene, propylene and optionally a diene.Desirably, the polymers of the invention have a weight average molecularweight (Mw) from 10,000 to 2,500,000, a polydispersity less than 3.5,more preferably less than 3.0, and a Mooney viscosity (ML (1+4) 125° C.)from 1 to 250.

More preferably, such polymers have an ethylene content from 10 to 98percent, a diene content from 0 to 6 percent, an α-olefin content from 2to 90 percent, a Mw from 20,000 to 250,000, a polydispersity from 1.5 to3.0, and a Mooney viscosity from 10 to 100. Especially preferredinterpolymers are propylene/ethylene copolymers containing greater than10 percent ethylene, preferably greater than 15 percent ethylene, andhaving a pellet blocking strength less than or equal to 3 kPa and or acompression set less than or equal to 50 percent at 23° C.

The polymer may be oil extended with from 5 to 75 percent, preferablyfrom 10 to 60 percent, more preferably from 20 to 50 percent, based ontotal composition weight, of a processing oil. Suitable oils include anyoil that is conventionally used in manufacturing extended EPDM rubberformulations. Examples include both naphthenic- and paraffinic-oils,with paraffinic oils being preferred.

Highly desirably a curable EPDM rubber formulation is prepared byincorporation of one or more curing agents along with conventionalaccelerators or other adjuvants. Suitable curing agents are sulfurbased. Examples of suitable sulfur based curing agents include, but arenot limited to, sulfur, tetramethylthiuram disulfide (TMTD),dipentamethylenethiuram tetrasulfide (DPTT), 2-mercaptobenzothiazole(MBT), 2-mercaptobenzothiazolate disulfide (MBTS),zinc-2-mercaptobenozothiazolate (ZMBT), zinc diethyldithiocarbamatezinc(ZDEC), zinc dibutyldithiocarbamate (ZDBC), dipentamethylenethiuramtetrasulfide (DPTT), N-t-butylbenzothiazole-2-sulfanamide (TBBS), andmixtures thereof. A preferred cure system includes a combination ofsulfur, MBT and TMTD. Desirably, the foregoing components are employedin amounts from 0.1 to 5 percent, based on total composition weight.

A preferred elastomer composition according to this embodiment of theinvention may also include carbon black. Preferably, the carbon black ispresent in the amount of from 10 to 80 percent, more preferably from 20to 60 percent, based on total composition weight.

Additional components of the present formulations usefully employedaccording to the present invention include various other ingredients inamounts that do not detract from the properties of the resultantcomposition. These ingredients include, but are not limited to,activators such as calcium or magnesium oxide; fatty acids such asstearic acid and salts thereof; fillers and reinforcers such as calciumor magnesium carbonate, silica, and aluminum silicates; plasticizerssuch as dialkyl esters of dicarboxylic acids; antidegradants; softeners;waxes; and pigments.

Applications and End Uses

The polymers of the invention can be usefully employed in a variety ofconventional thermoplastic fabrication processes to produce usefularticles, including objects comprising at least one film layer, such asa monolayer film, or at least one layer in a multilayer film prepared bycast, blown, calendered, or extrusion coating processes; moldedarticles, such as blow molded, injection molded, or rotomolded articles;extrusions; fibers; and woven or non-woven fabrics. Thermoplasticcompositions comprising the present polymers, include blends with othernatural or synthetic polymers, additives, reinforcing agents, ignitionresistant additives, antioxidants, stabilizers, colorants, extenders,crosslinkers, blowing agents, and plasticizers. Of particular utilityare multi-component fibers such as core/sheath fibers, having an outersurface layer, comprising at least in part, one or more polymers of theinvention.

Fibers that may be prepared from the present polymers or blends includestaple fibers, tow, multicomponent, sheath/core, twisted, andmonofilament. Suitable fiber forming processes include spinbonded, meltblown techniques, as disclosed in U.S. Pat. Nos. 4,430,563, 4, 663,220,4,668,566, and 4,322,027, gel spun fibers as disclosed in U.S. Pat. No.4,413,110, woven and nonwoven fabrics, as disclosed in U.S. Pat. No.3,485,706, or structures made from such fibers, including blends withother fibers, such as polyester, nylon or cotton, thermoformed articles,extruded shapes, including profile extrusions and co-extrusions,calendared articles, and drawn, twisted, or crimped yarns or fibers. Thenew polymers described herein are also useful for wire and cable coatingoperations, as well as in sheet extrusion for vacuum forming operations,and forming molded articles, including the use of injection molding,blow molding process, or rotomolding processes. Compositions comprisingthe olefin polymers can also be formed into fabricated articles such asthose previously mentioned using conventional polyolefin processingtechniques which are well known to those skilled in the art ofpolyolefin processing.

Dispersions (both aqueous and non-aqueous) can also be formed using thepresent polymers or formulations comprising the same. Frothed foamscomprising the invented polymers can also be formed, as disclosed in PCTapplication No. 2004/027593, filed Aug. 25, 2004. The polymers may alsobe crosslinked by any known means, such as the use of peroxide, electronbeam, silane, azide, or other cross-linking technique. The polymers canalso be chemically modified, such as by grafting (for example by use ofmaleic anhydride (MAH), silanes, or other grafting agent), halogenation,amination, sulfonation, or other chemical modification.

Additives and adjuvants may be included in any formulation comprisingthe present polymers. Suitable additives include fillers, such asorganic or inorganic particles, including clays, talc, titanium dioxide,zeolites, powdered metals, organic or inorganic fibers, including carbonfibers, silicon nitride fibers, steel wire or mesh, and nylon orpolyester cording, nano-sized particles, clays, and so forth;tackifiers, oil extenders, including paraffinic or napthelenic oils; andother natural and synthetic polymers, including other polymers accordingto the invention.

Suitable polymers for blending with the polymers of the inventioninclude thermoplastic and non-thermoplastic polymers including naturaland synthetic polymers. Exemplary polymers for blending includepolypropylene, (both impact modifying polypropylene, isotacticpolypropylene, atactic polypropylene, and random ethylene/propylenecopolymers), various types of polyethylene, including high pressure,free-radical LDPE, Ziegler Natta LLDPE, metallocene PE, includingmultiple reactor PE (“in reactor” blends of Ziegler-Natta PE andmetallocene PE, such as products disclosed in U.S. Pat. Nos. 6,545,088,6,538,070, 6,566,446, 5,844,045, 5,869,575, and 6,448,341,ethylene-vinyl acetate (EVA), ethylene/vinyl alcohol copolymers,polystyrene, impact modified polystyrene, ABS, styrene/butadiene blockcopolymers and hydrogenated derivatives thereof (SBS and SEBS), andthermoplastic polyurethanes. Homogeneous polymers such as olefinplastomers and elastomers, ethylene and propylene-based copolymers (forexample polymers available under the trade designation VERSIFY™available from The Dow Chemical Company and VISTAMAXX™ available fromExxonMobil can also be useful as components in blends comprising thepresent polymers.

Suitable end uses for the foregoing products include films and fibers;molded articles, such as tooth brush handles and appliance handles;gaskets and profiles; adhesives (including hot melt adhesives andpressure sensitive adhesives); footwear (including shoe soles and shoeliners); auto interior parts and profiles; foam goods (both open andclosed cell); impact modifiers for other thermoplastic polymers such asEPDM, isotactic polypropylene, or other olefin polymers; coated fabrics;hoses; tubing; weather stripping; cap liners; flooring; and viscosityindex modifiers, also known as pour point modifiers, for lubricants.

In a highly desired embodiment of the invention thermoplasticcompositions comprising a thermoplastic matrix polymer, especiallyisotactic polypropylene, and an elastomeric pseudo-block copolymeraccording to the invention, are uniquely capable of forming core-shelltype particles having hard crystalline or semi-crystalline blocks in theform of a core surrounded by soft or elastomeric blocks forming a“shell” around the occluded domains of hard polymer. These particles areformed and dispersed within the matrix polymer by the forces incurredduring melt compounding or blending. This highly desirable morphology isbelieved to result due to the unique physical properties of themulti-block copolymers which enable compatible polymer regions such asthe matrix and higher comonomer content elastomeric regions of thepseudo-block copolymer to self-assemble in the melt due to thermodynamicforces. Shearing forces during compounding are believed to produceseparated regions of matrix polymer encircled by elastomer. Uponsolidifying, these regions become occluded elastomer particles encasedin the polymer matrix.

Particularly desirable blends are thermoplastic polyolefin blends (TPO),thermoplastic elastomer blends (TPE), thermoplastic vulcanisites (TPV)and styrenic polymer blends. TPE and TPV blends may be prepared bycombining the invented pseudo-block polymers, including functionalizedor unsaturated derivatives thereof with an optional rubber, includingconventional block copolymers, especially an SBS block copolymer, andoptionally a crosslinking or vulcanizing agent. TPO blends are generallyprepared by blending the invented pseudo-block copolymers with apolyolefin, and optionally a crosslinking or vulcanizing agent. Theforegoing blends may be used in forming a molded object, and optionallycrosslinking the resulting molded article. A similar procedure usingdifferent components has been previously disclosed in U.S. Pat. No.6,797,779.

Suitable conventional block copolymers for this application desirablypossess a Mooney viscosity (ML 1+4@100° C.) in the range from 10 to 135,more preferably from 25 to 100, and most preferably from 30 to 80.Suitable polyolefins especially include linear or low densitypolyethylene, polypropylene (including atactic, isotactic, syndiotacticand impact modified versions thereof) and poly(4-methyl-1-pentene).Suitable styrenic polymers include polystyrene, rubber modifiedpolystyrene (HIPS), styrene/acrylonitrile copolymers (SAN), rubbermodified SAN (ABS or AES) and styrene maleic anhydride copolymers.

The blends may be prepared by mixing or kneading the respectivecomponents at a temperature around or above the melt point temperatureof one or both of the components. For most multiblock copolymers, thistemperature may be above 130° C., most generally above 145° C., and mostpreferably above 150° C. Typical polymer mixing or kneading equipmentthat is capable of reaching the desired temperatures and meltplastifying the mixture may be employed. These include mills, kneaders,extruders (both single screw and twin-screw), Banbury mixers, andcalenders. The sequence of mixing and method may depend on the finalcomposition. A combination of Banbury batch mixers and continuous mixersmay also be employed, such as a Banbury mixer followed by a mill mixerfollowed by an extruder. Typically, a TPE or TPV composition will have ahigher loading of cross-linkable polymer (typically the conventionalblock copolymer containing unsaturation) compared to TPO compositions.Generally, for TPE and TPV compositions, the weight ratio of blockcopolymer to pseudo-block copolymer should be from 90:10 to 10:90, morepreferably from 80:20 to 20:80, and most preferably from 75:25 to 25:50.For TPO applications, the weight ratio of pseudo-block copolymer topolyolefin may be from 49:51 to 5:95, more preferably from 35:65 to10:90. For modified styrenic polymer applications, the weight ratio ofpseudo-block copolymer to polyolefin may also be from 49:51 to 5:95,more preferably from 35:65 to 10:90. The ratios may be changed bychanging the viscosity ratios of the various components. There isconsiderable literature illustrating techniques for changing the phasecontinuity by changing the viscosity ratios of the constituents of ablend and a person skilled in this art may consult if necessary.

The blend compositions may contain processing oils, plasticizers, andprocessing aids. Rubber processing oils have a certain ASTM designationsand paraffinic, napthenic or aromatic process oils are all suitable foruse. Generally from 0 to 150 parts, more preferably 0 to 100 parts, andmost preferably from 0 to 50 parts of oil per 100 parts of total polymerare employed. Higher amounts of oil may tend to improve the processingof the resulting product at the expense of some physical properties.Additional processing aids include conventional waxes, fatty acid salts,such as calcium stearate or zinc stearate, (poly)alcohols includingglycols, (poly)alcohol ethers, including glycol ethers, (poly)esters,including (poly)glycol esters, and metal salt-, especially Group 1 or 2metal or zinc-, salt derivatives thereof.

It is known that non-hydrogenated rubbers such as those comprisingpolymerized forms of butadiene or isoprene, including block copolymers(here-in-after diene rubbers), have lower resistance to UV, ozone, andoxidation, compared to mostly or highly saturated rubbers. Inapplications such as tires made from compositions containing higherconcentrations of diene based rubbers, it is known to incorporate carbonblack to improve rubber stability, along with anti-ozone additives orantioxidants. Pseudo-block copolymers according to the present inventionpossess extremely low levels of unsaturation, and find particularapplication as a protective surface layer (coated, coextruded orlaminated) or weather resistant film adhered to articles formed fromconventional diene elastomer modified polymeric compositions.

For certain of the present TPO, TPV, and TPE applications, carbon blackis the additive of choice for UV absorption and stabilization.Representative examples of carbon blacks include ASTM N110, N121, N220,N231, N234, N242, N293, N299, S315, N326, N330, M332, N339, N343, N347,N351, N358, N375, N539, N550, N582, N630, N642, N650, N683, N754, N762,N765, N774, N787, N907, N908, N990 and N991. These carbon blacks haveiodine absorptions ranging from 9 to 145 g/kg and average pore volumesranging from 10 to 150 cm³/100 g. Generally, smaller particle sizedcarbon blacks are employed, to the extent cost considerations permit.For many such applications the present pseudo-block copolymers andblends thereof require little or no carbon black, thereby allowingconsiderable design freedom to include alternative pigments or nopigments at all.

Compositions, including thermoplastic blends according to the inventionmay also contain anti-ozonants and anti-oxidants that are known to arubber chemist of ordinary skill. The anti-ozonants may be physicalprotectants such as waxy materials that come to the surface and protectthe part from oxygen or ozone or they may be chemical protectors thatreact with oxygen or ozone. Suitable chemical protectors includestyrenated phenols, butylated octylated phenol, butylateddi(dimethylbenzyl)phenol, p-phenylenediamines, butylated reactionproducts of p-cresol and dicyclopentadiene (DCPD), polyphenolicanitioxidants, hydroquinone derivatives, quinoline, diphenyleneantioxidants, thioester antioxidants, and blends thereof. Somerepresentative trade names of such products are Wingstay™ S antioxidant,Polystay™ 100 antioxidant, Polystay™ 100 AZ antioxidant, Polystay™ 200antioxidant, Wingstay™ L antioxidant, Wingstay™ LHLS antioxidant,Wingstay™ K antioxidant, Wingstay™ 29 antioxidant, Wingstay™ SN-1antioxidant, and Irganox™ antioxidants. In some applications, theantioxidants and antiozonants used will preferably be non-staining andnon-migratory.

For providing additional stability against UV radiation, hindered aminelight stabilizers (HALS) and UV absorbers may be also used. Suitableexamples include Tinuvin™ 123, Tinuvin™ 144, Tinuvin™ 622, Tinuvin™ 765,Tinuvin™ 770, and Tinuvin™ 780, available from Ciba Specialty Chemicals,and Chemisorb™ T944, available from Cytex Plastics, Houston, Tex., USA.A Lewis acid may be additionally included with a HALS compound in orderto achieve superior surface quality, as disclosed in U.S. Pat. No.6,051,681.

For some compositions, additional mixing process may be employed topre-disperse the anti-oxidants, anti-ozonants, carbon black, UVabsorbers, and/or light stabilizers to form a masterbatch, andsubsequently to form polymer blends there from.

Suitable crosslinking agents (also referred to as curing or vulcanizingagents) for use herein include sulfur based, peroxide based, or phenolicbased compounds. Examples of the foregoing materials are found in theart, including in U.S. Pat. Nos. 3,758,643, 3,806,558, 5,051,478,4,104,210, 4,130,535, 4,202,801, 4,271,049, 4,340,684, 4,250,273,4,927,882, 4,311,628 and 5,248,729.

When sulfur based curing agents are employed, accelerators and cureactivators may be used as well. Accelerators are used to control thetime and/or temperature required for dynamic vulcanization and toimprove the properties of the resulting cross-linked article. In oneembodiment, a single accelerator or primary accelerator is used. Theprimary accelerator(s) may be used in total amounts ranging from 0.5 to4, preferably 0.8 to 1.5, phr, based on total composition weight. Inanother embodiment, combinations of a primary and a secondaryaccelerator might be used with the secondary accelerator being used insmaller amounts, such as from 0.05 to 3 phr, in order to activate and toimprove the properties of the cured article. Combinations ofaccelerators generally produce articles having properties that aresomewhat better than those produced by use of a single accelerator. Inaddition, delayed action accelerators may be used which are not affectedby normal processing temperatures yet produce a satisfactory cure atordinary vulcanization temperatures. Vulcanization retarders might alsobe used. Suitable types of accelerators that may be used in the presentinvention are amines, disulfides, guanidines, thioureas, thiazoles,thiurams, sulfenamides, dithiocarbamates and xanthates. Preferably, theprimary accelerator is a sulfenamide. If a second accelerator is used,the secondary accelerator is preferably a guanidine, dithiocarbamate orthiuram compound. Certain processing aids and cure activators such asstearic acid and ZnO may also be used. When peroxide based curing agentsare used, co-activators or coagents may be used in combinationtherewith. Suitable coagents include trimethylolpropane triacrylate(TMPTA), trimethylolpropane trimethacrylate (TMPTMA), triallyl cyanurate(TAC), triallyl isocyanurate (TAIC), among others. Use of peroxidecrosslinkers and optional coagents used for partial or complete dynamicvulcanization are known in the art and disclosed for example in thepublication, “Peroxide Vulcanization of Elastomers”, Vol. 74, No 3,July-August 2001.

When the pseudo-block copolymer containing composition is at leastpartially crosslinked, the degree of crosslinking may be measured bydissolving the composition in a solvent for specified duration, andcalculating the percent gel or unextractable rubber. The percent gelnormally increases with increasing crosslinking levels. For curedarticles according to the invention, the percent gel content isdesirably in the range from 5 to 100 percent.

The pseudo-block copolymers of the invention as well as blends thereofpossess improved processability compared to prior art compositions, due,it is believed, to lower melt viscosity. Thus, the composition or blenddemonstrates an improved surface appearance, especially when formed intoa molded or extruded article. At the same time, the present compositionsand blends thereof uniquely possess improved melt strength properties,thereby allowing the present pseudo-block copolymers and blends thereof,especially TPO blends, to be usefully employed in foam and inthermoforming applications where melt strength is currently inadequate.

Thermoplastic compositions according to the invention may also containorganic or inorganic fillers or other additives such as starch, talc,calcium carbonate, glass fibers, polymeric fibers (including nylon,rayon, cotton, polyester, and polyaramide), metal fibers, flakes orparticles, expandable layered silicates, phosphates or carbonates, suchas clays, mica, silica, alumina, aluminosilicates or aluminophosphates,carbon whiskers, carbon fibers, nanoparticles including nanotubes,wollastonite, graphite, zeolites, and ceramics, such as silicon carbide,silicon nitride or titanias. Silane based or other coupling agents mayalso be employed for better filler bonding.

The thermoplastic compositions of this invention, including theforegoing blends, may be processed by conventional molding techniquessuch as injection molding, extrusion molding, thermoforming, slushmolding, over molding, insert molding, blow molding, and othertechniques. Films, including multi-layer films, may be produced by castor tentering processes, including blown film processes.

Testing Methods

In the foregoing characterizing disclosure and the examples that follow,the following analytical techniques are employed:

Standard CRYSTAF Method

Branching distributions are determined by crystallization analysisfractionation (CRYSTAF) using a CRYSTAF 200 unit commercially availablefrom PolymerChar, Valencia, Spain. The samples are dissolved in 1,2,4trichlorobenzene at 160° C. (0.66 mg/mL) for 1 hr and stabilized at 95°C. for 45 minutes. The sampling temperatures range from 95 to 30° C. ata cooling rate of 0.2° C./min. An infrared detector is used to measurethe polymer solution concentrations. The cumulative solubleconcentration is measured as the polymer crystallizes while thetemperature is decreased. The analytical derivative of the cumulativeprofile reflects the short chain branching distribution of the polymer.

The CRYSTAF peak temperature and area are identified by the peakanalysis module included in the CRYSTAF Software (Version 2001.b,PolymerChar, Valencia, Spain). The CRYSTAF peak finding routineidentifies a peak temperature as a maximum in the dW/dT and the areabetween the largest positive inflections on either side of theidentified peak in the derivative curve.

DSC Standard Method

Differential Scanning Calorimetry results are determined using a TAImodel Q1000 DSC equipped with an RCS cooling accessory and anautosampler. A nitrogen purge gas flow of 50 ml/min is used. The sampleis pressed into a thin film and melted in the press at 175° C. and thenair-cooled to room temperature (25° C.). 10 mg of material in the formof a 5-6 mm diameter disk is accurately weighed and placed in analuminum foil pan (ca 50 mg) which is then crimped shut. The thermalbehavior of the sample is investigated with the following temperatureprofile. The sample is rapidly heated to 180° C. and held isothermal for3 minutes in order to remove any previous thermal history. The sample isthen cooled to −40° C. at 10° C./min cooling rate and held at −40° C.for 3 minutes. The sample is then heated to 150° C. at 10° C./min.heating rate. The cooling and second heating curves are recorded.

The DSC melting peak is measured as the maximum in heat flow rate (W/g)with respect to the linear baseline drawn between −30° C. and end ofmelting. The heat of fusion is measured as the area under the meltingcurve between −30° C. and the end of melting using a linear baseline.

Abrasion Resistance

Abrasion resistance is measured on compression molded plaques accordingto ISO 4649. The average value of 3 measurements is reported. Plaques of6.4 mm thick are compression molded using a hot press (Carver Model#4095-4PR100R). The pellets are placed between polytetrafluoroethylenesheets, heated at 190° C. at 55 psi (380 kPa) for 3 min, followed by 1.3MPa for 3 min, and then 2.6 MPa for 3 min. Next the film is cooled inthe press with running cold water at 1.3 MPa for 1 min.

GPC Method

The gel permeation chromatographic system consists of either a PolymerLaboratories Model PL-210 or a Polymer Laboratories Model PL-220instrument. The column and carousel compartments are operated at 140° C.Three Polymer Laboratories 10-micron Mixed-B columns are used. Thesolvent is 1,2,4 trichlorobenzene. The samples are prepared at aconcentration of 0.1 grams of polymer in 50 milliliters of solventcontaining 200 ppm of butylated hydroxytoluene (BHT). Samples areprepared by agitating lightly for 2 hours at 160° C. The injectionvolume used is 100 microliters and the flow rate is 1.0 ml/minute.

Calibration of the GPC column set is performed with 21 narrow molecularweight distribution polystyrene standards with molecular weights rangingfrom 580 to 8,400,000, arranged in 6 “cocktail” mixtures with at least adecade of separation between individual molecular weights. The standardsare purchased from Polymer Laboratories (Shropshire, UK). Thepolystyrene standards are prepared at 0.025 grams in 50 milliliters ofsolvent for molecular weights equal to or greater than 1,000,000, and0.05 grams in 50 milliliters of solvent for molecular weights less than1,000,000. The polystyrene standards are dissolved at 80° C. with gentleagitation for 30 minutes. The narrow standards mixtures are run firstand in order of decreasing highest molecular weight component tominimize degradation. The polystyrene standard peak molecular weightsare converted to polyethylene molecular weights using the followingequation (as described in Williams and Ward, J. Polym. Sci., Polym.Let., 6, 621 (1968)): M_(polyethylene)=0.431(M_(polystyrene)).

Polyetheylene equivalent molecular weight calculations are performedusing Viscotek TriSEC software Version 3.0.

Compression Set

Compression set is measured according to ASTM D 395. The sample isprepared by stacking 25.4 mm diameter round discs of 3.2 mm, 2.0 mm, and0.25 mm thickness until a total thickness of 12.7 mm is reached. Thediscs are cut from 12.7 cm×12.7 cm compression molded plaques moldedwith a hot press under the following conditions: zero pressure for 3 minat 190° C., followed by 86 MPa for 2 min at 190° C., followed by coolinginside the press with cold running water at 86 MPa.

Density

Density measurement are conducted according to ASTM D 1928. Measurementsare made within one hour of sample pressing using ASTM D792, Method B.

Flexural/Secant Modulus

Samples are compression molded using ASTM D 1928. Flexural and 2 percentsecant moduli are measured according to ASTM D-790.

Optical Properties, Tensile, Hysteresis, and Tear

Films of 0.4 mm thickness are compression molded using a hot press(Carver Model #4095-4PR1001R). The pellets are placed betweenpolytetrafluoroethylene sheets, heated at 190° C. at 55 psi (380 kPa)for 3 min, followed by 1.3 MPa for 3 min, and then 2.6 MPa for 3 min.The film is then cooled in the press with running cold water at 1.3 MPafor 1 min. The compression molded films are used for opticalmeasurements, tensile behavior, recovery, and stress relaxation.

Clarity is measured using BYK Gardner Haze-gard as specified in ASTM D1746.

45° gloss is measured using BYK Gardner Glossmeter Microgloss 45° asspecified in ASTM D-2457

Internal haze is measured using BYK Gardner Haze-gard based on ASTM D1003 Procedure A. Mineral oil is applied to the film surface to removesurface scratches.

Stress-strain behavior in uniaxial tension is measured using ASTM D 1708microtensile specimens. Samples are stretched with an Instron at 500%min⁻¹ at 21° C. Tensile strength and elongation at break are reportedfrom an average of 5 specimens.

100% and 300% Hysteresis is determined from cyclic loading to 100% and300% strains according to ASTM D 1708 with an Instron™ instrument. Thesample is loaded and unloaded at 267% min⁻¹ for 3 cycles at 21° C.Cyclic experiments at 300% and 80° C. are conducted using anenvironmental chamber. In the 80° C. experiment, the sample is allowedto equilibrate for 45 minutes at the test temperature before testing. Inthe 21° C., 300% strain cyclic experiment, the retractive stress at 150%strain from the first unloading cycle is recorded. Percent recovery forall experiments are calculated from the first unloading cycle using thestrain at which the load returned to the base line. The percent recoveryis defined as:

${\%\mspace{14mu}{Recovery}} = {\frac{ɛ_{f} - ɛ_{s}}{ɛ_{f}} \times 100}$

where ε_(f) is the strain taken for cyclic loading and ε_(s) is thestrain where the load returns to the baseline during the 1^(st)unloading cycle.

Stress relaxation is measured at 50 percent strain and 37° C. for 12hours using an Instron™ instrument equipped with an environmentalchamber. The gauge geometry was 76 mm×25 mm×0.4 mm. After equilibratingat 37° C. for 45 min in the environmental chamber, the sample wasstretched to 50% strain at 333% min⁻¹. Stress was recorded as a functionof time for 12 hours. The percent stress relaxation after 12 hours wascalculated using the formula:

${\%\mspace{14mu}{Stress}\mspace{14mu}{Relaxation}} = {\frac{L_{0} - L_{12}}{L_{0}} \times 100}$where L₀ is the load at 50% strain at 0 time and L₁₂ is the load at 50percent strain after 12 hours.

Tensile notched tear experiments are carried out on samples having adensity of 0.88 g/cc or less using an Instron™ instrument. The geometryconsists of a gauge section of 76 mm×13 mm×0.4 mm with a 2 mm notch cutinto the sample at half the specimen length. The sample is stretched at508 mm min⁻¹ at 21° C. until it breaks. The tear energy is calculated asthe area under the stress-elongation curve up to strain at maximum load.An average of at least 3 specimens are reported.

TMA

Thermal Mechanical Analysis is conducted on 30 mm diameter×3.3 mm thick,compression molded discs, formed at 180° C. and 10 MPa molding pressurefor 5 minutes and then air quenched. The instrument used is a TMA 7,brand available from Perkin-Elmer. In the test, a probe with 1.5 mmradius tip (P/N N519-0416) is applied to the surface of the sample discwith 1N force. The temperature is raised at 5° C./min from 25° C. Theprobe penetration distance is measured as a function of temperature. Theexperiment ends when the probe has penetrated 1 mm into the sample.

DMA

Dynamic Mechanical Analysis (DMA) is measured on compression moldeddisks formed in a hot press at 180° C. at 10 MPa pressure for 5 minutesand then water cooled in the press at 90° C./min. Testing is conductedusing an ARES controlled strain rheometer (TA instruments) equipped withdual cantilever fixtures for torsion testing.

A 1.5 mm plaque is pressed and cut in a bar of dimensions 32×12 mm. Thesample is clamped at both ends between fixtures separated by 10 mm (gripseparation ΔL) and subjected to successive temperature steps from −100°C. to 200° C. (5° C. per step). At each temperature the torsion modulusG′ is measured at an angular frequency of 10 rad/s, the strain amplitudebeing maintained between 0.1 percent and 4 percent to ensure that thetorque is sufficient and that the measurement remains in the linearregime.

An initial static force of 10 g is maintained (auto-tension mode) toprevent slack in the sample when thermal expansion occurs. As aconsequence, the grip separation ΔL increases with the temperature,particularly above the melting or softening point of the polymer sample.The test stops at the maximum temperature or when the gap between thefixtures reaches 65 mm.

Pellet Blocking Behavior

Pellets (150 g) are loaded into a 2″ (5 cm) diameter hollow cylinderthat is made of two halves held together by a hose clamp. A 2.75 lb(1.25 kg) load is applied to the pellets in the cylinder at 45° C. for 3days. After 3 days, the pellets loosely consolidate into a cylindricalshaped plug. The plug is removed from the form and the pellet blockingforce measured by loading the cylinder of blocked pellets in compressionusing an Instron™ instrument to measure the compressive force needed tobreak the cylinder into pellets.

Melt Properties

Melt Flow Rate (MFR) and Melt index, or 12, are measured in accordancewith ASTM D1238, Condition 190° C./2.16 kg.

ATREF

Analytical temperature rising elution fractionation (ATREF) analysis isconducted according to the method described in U.S. Pat. No. 4,798,081.The composition to be analyzed is dissolved in trichlorobenzene andallowed to crystallize in a column containing an inert support(stainless steel shot) by slowly reducing the temperature to 20° C. at acooling rate of 0.1° C./min. The column is equipped with an infrareddetector. An ATREF chromatogram curve is then generated by eluting thecrystallized polymer sample from the column by slowly increasing thetemperature of the eluting solvent (trichlorobenzene) from 20 to 120° C.at a rate of 1.5° C./min.

SPECIFIC EMBODIMENTS

The following specific embodiments of the invention and combinationsthereof are especially desirable and hereby delineated in order toprovide detailed disclosure for the appended claims.

1. A process for the polymerization of one or more additionpolymerizable monomers, preferably two or more addition polymerizablemonomers, especially ethylene and at least one copolymerizablecomonomer, propylene and at least one copolymerizable comonomer, or4-methyl-1-pentene and at least one copolymerizable comonomer, to form acopolymer comprising multiple regions or segments of differentiatedpolymer composition or properties, especially regions comprisingdiffering comonomer incorporation index, said process comprisingcontacting an addition polymerizable monomer or mixture of monomersunder addition polymerization conditions with a composition comprisingat least one olefin polymerization catalyst, a cocatalyst and a chainshuttling agent, said process being characterized by formation of atleast some of the growing polymer chains under differentiated processconditions such that two or more blocks or segments formed within atleast some of the resulting polymer are chemically or physicallydistinguishable.

2. A high molecular weight copolymer, especially such a copolymercomprising in polymerized form ethylene and a copolymerizable comonomer,propylene and at least one copolymerizable comonomer, or4-methyl-1-pentene and at least one copolymerizable comonomer, saidcopolymer comprising two or more intramolecular regions or segmentscomprising differing chemical or physical properties, especially regionsor segments of differentiated comonomer incorporation. Highly preferablythe copolymer possesses a molecular weight distribution, Mw/Mn, of lessthan 3.0, preferably less than 2.8.

3. A polymer mixture comprising: (1) an organic or inorganic polymer,preferably a homopolymer of ethylene and/or a copolymer of ethylene anda copolymerizable comonomer, and (2) a copolymer according to thepresent invention or prepared according to the process of the presentinvention.

4. A process according to embodiment 1 wherein the catalyst comprises ametal complex corresponding to the formula:

wherein:

R¹¹ is selected from alkyl, cycloalkyl, heteroalkyl, cycloheteroalkyl,aryl, and inertly substituted derivatives thereof containing from 1 to30 atoms not counting hydrogen or a divalent derivative thereof;

T¹ is a divalent bridging group of from 1 to 41 atoms other thanhydrogen, preferably 1 to 20 atoms other than hydrogen, and mostpreferably a mono- or di-C₁₋₂₀ hydrocarbyl substituted methylene orsilane group; and

R¹² is a C₅₋₂₀ heteroaryl group containing Lewis base functionality,especially a pyridin-2-yl- or substituted pyridin-2-yl group or adivalent derivative thereof;

M¹ is a Group 4 metal, preferably hafnium;

X¹ is an anionic, neutral or dianionic ligand group;

x′ is a number from 0 to 5 indicating the number of such X¹ groups; and

bonds, optional bonds and electron donative interactions are representedby lines, dotted lines and arrows respectively.

4. A process according to embodiment 1 wherein the catalyst comprises ametal complex corresponding to the formula:

wherein

-   -   M² is a metal of Groups 4-10 of the Periodic Table of the        elements;    -   T² is a nitrogen, oxygen or phosphorus containing group;    -   X² is halo, hydrocarbyl, or hydrocarbyloxy;    -   t is one or two;    -   x″ is a number selected to provide charge balance;    -   and T² and N are linked by a bridging ligand.

The skilled artisan will appreciate that the invention disclosed hereinmay be practiced in the absence of any component which has not beenspecifically disclosed.

EXAMPLES

The following examples are provided as further illustration of theinvention and are not to be construed as limiting. The term “overnight”,if used, refers to a time of approximately 16-18 hours, the term “roomtemperature”, refers to a temperature of 20-25° C., and the term “mixedalkanes” refers to a commercially obtained mixture of C₆₋₉ aliphatichydrocarbons available under the trade designation Isopar E®, from ExxonMobil Chemicals Inc. In the event the name of a compound herein does notconform to the structural representation thereof, the structuralrepresentation shall control. The synthesis of all metal complexes andthe preparation of all screening experiments were carried out in a drynitrogen atmosphere using dry box techniques. All solvents used wereHPLC grade and were dried before their use.

MMAO refers to modified methylalumoxane, a triisobutylaluminum modifiedmethylalumoxane available commercially from Akzo-Noble Corporation.

Catalyst (A1) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-isopropylphenyl)(α-naphthalen-2-diyl(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740.

Catalyst (A2) is[N-(2,6-di(1-methylethyl)phenyl)amido)(2-methylphenyl)(1,2-phenylene-(6-pyridin-2-diyl)methane)]hafniumdimethyl, prepared according to the teachings of WO 03/40195,2003US0204017, U.S. Ser. No. 10/429,024, filed May 2, 2003, and WO04/24740.

Catalyst (A3) isbis[N,N′″-(2,4,6-tri(methylphenyl)amido)ethylenediamine]hafniumdibenzyl.

Catalyst (A4) isbis((2-oxoyl-3-(dibenzo-1H-pyrrole-1-yl)-5-(methyl)phenyl)-2-phenoxymethyl)cyclohexane-1,2-diylzirconium (IV) dibenzyl, prepared substantially according to theteachings of US-A-2004/0010103.

Catalyst (A5) is(bis-(1-methylethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconiumdibenzyl.

The preparation of catalyst (A5) is conducted as follows.

a) Preparation of (1-methylethyl)(2-hydroxy-3,5-di(t-butyl)phenyl)imine

3,5-Di-t-butylsalicylaldehyde (3.00 g) is added to 10 mL ofisopropylamine. The solution rapidly turns bright yellow. After stirringat ambient temperature for 3 hours, volatiles are removed under vacuumto yield a bright yellow, crystalline solid (97 percent yield).

b) Preparation of(bis-(1-methylethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino) zirconiumdibenzyl

A solution of (1-methylethyl)(2-hydroxy-3,5-di(t-butyl)phenyl)imine (605mg, 2.2 mmol) in 5 mL toluene is slowly added to a solution ofZr(CH₂Ph)₄ (500 mg, 1.1 mmol) in 50 mL toluene. The resulting darkyellow solution is stirred for 30 min. Solvent is removed under reducedpressure to yield the desired product as a reddish-brown solid.

Catalyst (A6) isbis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconium dibenzyl

The preparation of catalyst (A6) is conducted as follows.

a) Preparation of(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)imine

2-Methylcyclohexylamine (8.44 mL, 64.0 mmol) is dissolved in methanol(90 mL), and di-t-butylsalicaldehyde (10.00 g, 42.67 mmol) is added. Thereaction mixture is stirred for three hours and then cooled to −25° C.for 12 hrs. The resulting yellow solid precipitate is collected byfiltration and washed with cold methanol (2×15 mL), and then dried underreduced pressure. The yield is 11.17 g of a yellow solid. ¹H NMR isconsistent with the desired product as a mixture of isomers.

b) Preparation ofbis-(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)immino)zirconiumdibenzyl

A solution of(1-(2-methylcyclohexyl)ethyl)(2-oxoyl-3,5-di(t-butyl)phenyl)imine (7.63g, 23.2 mmol) in 200 mL toluene is slowly added to a solution ofZr(CH₂Ph)₄ (5.28 g, 11.6 mmol) in 600 mL toluene. The resulting darkyellow solution is stirred for 1 hour at 25° C. The solution is dilutedfurther with 680 mL toluene to give a solution having a concentration of0.00783 M.

Catalyst (A7) is(t-butylamido)dimethyl(3-N-pyrrolyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the techniques of U.S. Pat.No. 6,268,444:

Catalyst (A8) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,7a-η-inden-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286:

Catalyst (A9) is(t-butylamido)di(4-methylphenyl)(2-methyl-1,2,3,3a,8a-η-s-indacen-1-yl)silanetitaniumdimethyl prepared substantially according to the teachings ofUS-A-2003/004286:

Catalyst (A10) is bis(dimethyldisiloxane)(indene-1-yl)zirconiumdichloride available from Sigma-Aldrich:

Cocatalyst 1 A mixture of methyldi(C₁₄₋₁₈ alkyl)ammonium salts oftetrakis(pentafluorophenyl)borate (here-in-after armeenium borate),prepared by reaction of a long chain trialkylamine (Armeen™ M2HT,available from Akzo-Nobel, Inc.), HCl and Li[B(C₆F₅)₄], substantially asdisclosed in U.S. Pat. No. 5,919,983, Ex. 2.

Cocatalyst 2 Mixed C₁₄₋₁₈ alkyldimethylammonium salt ofbis(tris(pentafluorophenyl)-alumane)-2-undecylimidazolide, preparedaccording to U.S. Pat. No. 6,395,671, Ex. 16.

Shuttling Agents The shuttling agents employed include diethylzinc (DEZ,SA1), di(1-butyl)zinc (SA2), di(n-hexyl)zinc (SA3), triethylaluminum(TEA, SA4), trioctylaluminum (SA5), trimethylgallium (SA6),bis(t-butyldimethylsiloxy)i-butylaluminum (SA7),bis(di(trimethylsilyl)amido)isobutylaluminum (SA8),di(2-pyrridylmethoxy)_(n)-octylaluminum (SA9),bis(n-octadecyl)i-butylaluminum (SA10),bis(di(n-pentyl)amido)isobutylaluminum (SA11),bis(2,6-di-t-butylphenoxy)n-octylaluminum (SA 12),di(1-naphthyl)ethylamido)n-octylaluminum (SA13),bis(t-butyldimethylsiloxy)ethylaluminum (SA14),bis(di(trimethylsilyl)amido)ethyl-aluminum (SA 15),bis(2,3,6,7-dibenzoazacyclohexan-1-yl)ethylaluminum (SA16),bis(2,3,6,7-dibenzoazacyclohexan-1-yl)_(n)-octylaluminum (SA17),bis(dimethyl(t-butyl)siloxyl)_(n)-octyl-aluminum (SA18),ethyl(2,6-diphenylphenoxy)zinc (SA19), and ethyl(t-butoxy)zinc (SA20).

General High Throughput Parallel Polymerization Conditions

Polymerizations are conducted using a high throughput, parallelpolymerization reactor (PPR) available from Symyx technologies, Inc. andoperated substantially according to U.S. Pat. Nos. 6,248,540, 6,030,917,6,362,309, 6,306,658, and 6,316,663. Ethylene copolymerizations areconducted at 130° C. and 80 psi (550 kPa) with ethylene on demand using1.2 equivalents of cocatalyst 2 based on total catalyst used. A seriesof polymerizations are conducted in a parallel pressure reactor (PPR)comprised of 48 individual reactor cells in a 6×8 array that are fittedwith a pre-weighed glass tube. The working volume in each reactor cellis 6000 μL. Each cell is temperature and pressure controlled withstirring provided by individual stirring paddles. The monomer gas andquench gas (air) are plumbed directly into the PPR unit and controlledby automatic valves. Liquid reagents are robotically added to eachreactor cell by syringes and the reservoir solvent is mixed alkanes. Theorder of addition is mixed alkanes solvent (4 ml), ethylene, 1-octenecomonomer (143 mg), 0.419 μmol cocatalyst, shuttling agent in theindicated amounts, and finally, 0.3495 μmol catalyst A3. Afterquenching, the reactors are cooled and the glass tubes are unloaded. Thetubes are transferred to a centrifuge/vacuum drying unit, and dried for12 hours at 60° C. The tubes containing dried polymer are weighed andthe difference between this weight and the tare weight gives the netyield of polymer. Results are contained in Table 1.

Catalyst/Shuttling Agent Selection Method 1

A series of ethylene/1-octene polymerizations are conducted usingdiffering monomer conversions and one of two potential chain shuttlingagents, t-butyldimethylsiloxydi(isopropyl) aluminum (TSA, Runs A-F) anddiethylzinc (DEZ, Runs 1-6), using the foregoing high-throughputpolymerization technique. The resulting polymers are measured formolecular weight (Mw and Mn) using GPC. Polydispersity Index (PDI=Mw/Mn)is calculated for each polymer. Results are tabulated in Table 1

TABLE 1 Run Conversion (%) Yield Mw (g/mol) Mn (g/mol) Mw/Mn A 25 0.052495,202 159,079 3.11 B 51 0.086 455,178 103,781 4.39 C 75 0.102 490,448210,174 2.33 D 100 0.131 510,722 260,894 1.96 E 150 0.194 871,458194,801 4.47 F 184 0.235 605,453 137,957 4.39 1 26 0.0589 8,908 6,4771.38 2 52 0.0852 12,393 9,592 1.29 3 77 0.1173 16,570 13,176 1.26 4 1010.1416 21,387 17,397 1.23 5 151 0.1923 29,187 23,715 1.23 6 200 0.275241,043 32,203 1.27

It may be seen the polymers produced in Runs 1-6 have a relativelynarrow polydispersity (Mw/Mn) compared to polymers in the series A-F.This indicates that DEZ is an effective chain shuttling agent under theconditions of the polymerization, whereas TSA is not. Polymers preparedin a reactor, especially a loop, semi-batch, or plug flow type reactor,in a manner to expose an active catalyst site to at least two differentsets of reaction conditions, especially conditions encompassingdifferences in monomer/comonomer ratio, would therefore generate polymerproducts having multiple blocks or segments (pseudo-block copolymers).These polymers would be expected to possess properties resembling pureblock copolymers and distinguishable from those of random copolymers ofsimilar gross comonomer content.

Catalyst/Shuttling Agent Selection Method 2

The previously disclosed high throughput polymerization conditions aresubstantially repeated using various catalysts, cocatalyst 1, andpotential shuttling agents. Ethylene pressure is increased to 200 psi(1.4 MPa). Over 500 reactions are performed. The resultingethylene/1-octene copolymers are tested for Mn and PDI and polymerproduction rate compared to rates obtained from a control using MMAO inplace of the shuttling agent. The best compositions are then selectedbased on a combination of greatest molecular weight (Mn) reduction,greatest reduction in PDI, and least reduction (or actual increase) inpolymerization rate. Selected combinations showing the best results(ranked by Mn reduction) are presented in Table 2.

TABLE 2 Shuttling Run Catalyst Agent Relative Mn Relative PDI Relativerate i A1 SA7 0.07 0.88 1.33 ii ″ SA5 0.18 0.85 0.57 iii ″ SA15 0.190.93 6.29 iv A2 SA19 0.27 0.73 0.18 v A3 SA2 0.29 0.80 9.74 vi ″ SA80.38 1.01 1.15 vii ″ SA7 0.60 1.06 1.38 viii ″ SA11 0.65 1.04 1.43 ix ″SA3 0.65 0.86 4.61 x ″ SA17 0.66 0.95 6.36 xi ″ SA20 0.68 0.82 4.37 xiiA4 SA9 0.52 1.12 2.32 xiii ″ SA7 0.53 1.07 0.91 xiv ″ SA11 0.59 1.112.47 xv ″ SA14 0.69 1.07 2.12 xvi ″ SA18 0.69 1.10 3.16 xvii ″ SA12 0.701.07 0.97 xviii ″ SA5 0.93 0.95 0.81 xix A5 SA2 0.29 0.92 0.71 xx ″ SA130.59 0.97 0.93 xxi ″ SA3 0.63 0.95 0.93 xxii ″ SA5 0.79 1.10 1.19 xxiiiA6 SA13 0.83 0.92 0.67 xxiv A7 SA6 0.63 0.96 0.66 xv ″ SA7 0.74 1.150.96 xvi D1 SA14 0.54 1.10 1.14 xvii ″ SA10 0.59 1.10 0.77 xviii ″ SA50.74 1.01 0.72 xix ″ SA16 0.82 1.05 2.62

By reference to Table 2 a suitable combinations of catalyst andshuttling agent may be selected. It is to be emphasized that preferredcatalyst/shuttling agent combinations may in different embodiments, beselected based on a desired objective, such as maximum reduction in Mnor improvement in production rate coupled with more modest Mn reduction.Additionally, the above results are based on a batch reactor, whereas inpractice, the effect, if any, of using continuous polymerizationconditions must also be considered in selecting the final combination ofcatalysts and shuttling agent(s).

Continuous Solution Polymerization Reactions

Polymer samples according to the invention and comparative polymerexamples are prepared in a solution loop reactor using mixed alkanessolvent. Propylene, ethylene, hydrogen, catalyst package, and polymerare dissolved in the solvent during the polymerization process.Following the polymerization, the catalyst system is deactivated withwater. The resulting polymer is separated from the solvent by flashing,or devolatilization, of the solvent. The recovered solvent/propylenemixture is condensed, purified, and recycled to the reactor, operatingsubstantially according to the teachings of U.S. Pat. No. 6,355,741,5,977,251 or 5,684,097.

Referring to FIG. 2, the reactor 30, comprises a closed loop of highpressure piping such as a 3″ (7.5 cm) diameter, schedule 80 carbon steelpipe equipped with a circulation pump, 32, which circulates the reactorcontents (solvent, monomers, catalyst, and polymer) through the pipingand associated heat exchangers, 34 a and 34 b, flow meter, 36, andstatic mixing elements, 38 a, 38 b and 38 c. In operative communicationwith the reactor are inlets 52, for injection of monomer(s) andoptionally hydrogen, 54, for injection of catalyst, 56, for injection ofcocatalyst and optionally chain transfer agent, and 58, for injection ofmonomer(s), recycled process solvent (comprising unreacted monomer orcomonomer), and optionally hydrogen. Reactor outlet, 50, serves as aport for removal of the reactor contents and is in operativecommunication with a polymer recovery zone (not shown). After exitingthe reactor, polymer is separated from process solvent and unreactedmonomers in the recovery zone. Recovered process solvent and unreactedmonomer is reinjected into the reactor at inlets 52 or 58, or optionallyin varying amounts at both to provide ratios of recycled monomer at thetwo inlets from 1:99 to 99:1.

During operation, the ethylene and propylene concentrations in differentsections of the reactor are varied to create inhomogeneousconcentrations or gradients of monomer and comonomer within the reactor.This gradient is established by adjustments to pumping rate, reactorfeed splits, changing of monomer and commoner injection points, andmonomer conversions. For example, ethylene is added at a separateinjection point from the fresh comonomer addition point in order tocreate separate regions of differing concentrations of the two monomers.The amount of recycled process solvent injected with the ethylene mayalso be minimized in order to maximize the monomer/comonomer molar rationear the injection point of the reactor. In certain experiments, reducedpumping rates are also employed to decrease reactor mixing and maximizeethylene inhomogeneity within the loop reactor.

For the comparative examples, no chain shuttling agent is employed incombination with a poorly mixed reactor to create blends of polymershaving higher and lower crystallinity contents. For the examplesaccording to the invention, a chain shuttling agent is added. The chainshuttling agent creates a fraction of polymer molecules containingsegments of polymer made in both ethylene rich and ethylene poor regionsof the reactor. In one embodiment of the invention, the chain shuttlingagent is injected near to the point of lowest ethylene concentration,thereby resulting in the generation of a higher concentration of polymerin which the chain ends comprise higher crystallinity (low ethylenecontent) polymer. Results are provided in Tables 3, 4 and 5.

Examples 1-6 Comparative Examples A-B

Examples 1-6 and comparative examples A and B are carried out with thefollowing reagents and conditions: catalyst A1, cocatalyst 1, chainshuttling agent, SA1 (DEZ), polymerization temperature, 105° C., reactorpressure, 540 psig (3.7 MPa), total solvent flow, 1003 pounds/hour (455kg/hr), propylene conversion, 64 percent, solution density, 41 lb/ft³(656 kg/m³), and percent solids in reactor, 19 percent. Additionalprocess details are as follows:

Comparative A. The reactor is configured with all the ethylene enteringthe reactor at one point. No chain shuttling agent is employed. An 8percent ethylene content propylene/ethylene copolymer is prepared havinga melt flow rate of approximately 8 dg/min.

Example 1

Chain shuttling agent SA1 is introduced into the reactor whilemaintaining the reactor at a constant log(viscosity) the same as for the8MFR resin produced in Comparative A and discontinuing hydrogenaddition. The resulting resin, on hydrolysis of the feed stream,exhibits a MFR of approximately 14. The discrepancy between measuredreactor viscosity or molecular weight and ultimate product molecularweight indicates the presence of some fraction of (polymer)₂Zn speciesin the reactor, thereby indicating that chain shuttling is occurring inthe reactor.

Example 2

The reaction conditions of Example 1 are altered by reducing the flow ofchain shuttling agent until a product having a melt flow rate of 8dg/min is obtained.

Example 3

The reaction conditions of Example 2 are altered by reducing the pumpingrate to maximize the ethylene gradient in the reactor while stillensuring that the reactor contents remained soluble in the diluent. Theother flows are maintained as in example 2. The resulting polymer has ameasured MFR of approximately 5.

Example 4

The reaction conditions of Example 3 are altered by increasing the flowof chain shuttling agent until a product having a measured melt flowrate of approximately 8 is again obtained.

Example 5

The reaction conditions of Example 4 are altered by increasing theethylene flow to produce a target polymer comprising approximately 15percent polymerized ethylene. The chain shuttle agent flow is maintainedat the same level but the hydrogen flow to the reactor is increased inorder to maintain a product having approximately 8 MFR.

Example 6

The reaction conditions of Example 5 are altered by increasing ethyleneflow thereby producing a product having an ethylene content ofapproximately 20 percent.

Comparative B. The reaction conditions of Example 6 are altered bystopping the flow of chain shuttling agent and increasing hydrogen flowin order to produce a copolymer having a MFR of approximately 8 dg/min.while maintaining an ethylene content of 20 percent.

TABLE 3 Process Conditions Fresh Fresh Total propylene ethylenepropylene Fresh H₂ Log Catalyst Catalyst Cocat. Cocat. SA SA feed feedfeed Split feed flow viscosity concentration flow conc. flow conc. flowRecycle Ex. (pph) (pph) (pph) (top/bottom) (pph) (logCp) (ppm Hf)) (pph)(ppm) (pph) (ppm Zn) (pph) ratio A* 201 16.59 285 85/25 2061 2.79 5211.40 8598 0.63 0 0 9.90 1 ″ 17.47 286 ″ 0 2.82 ″ 2.49 ″ 1.11 5500 2.009.75 2 ″ 17.50 283 ″ ″ 3.02 ″ 2.52 ″ 1.13 ″ 1.77 9.80 3 ″ 17.49 284 ″ ″3.27 ″ 2.24 ″ 1.00 ″ 1.57 7.80 4 ″ ″ 283 ″ ″ 3.02 490 2.34 ″ 0.98 50001.92 ″ 5 178 30.18 260 72/28 1002 3.01 ″ 1.61 8598 0.68 ″ 1.33 7.70 6162 40.29 244 62/38 2212 2.90 ″ 1.32 7659 0.62 ″ 1.09 ″ B* ″ 40.21 240 ″4458 2.85 ″ 0.94 ″ 0.45 0 0 7.60 Feed split top/bottom, refers to thepercentage of propylene injected in the form of recycledsolvent/propylene mixture (bottom number).

TABLE 4 Polymer Physical Properties Ethylene Density MFR Tc Tm ΔH Cryst.Mw Mw/ Ex. Content (percent) (g/cm³) (dg/min) (° C.) (° C.) (J/g) (%)(×10³) Mn A*  8 0.8792 9.5 68 121 55 33 209 2.4 1 ″ 0.8791 14.9 62 12054 33 179 2.5 2 ″ 0.8795 9.3 61 118 53 32 201 2.5 3 ″ 0.9793 5.5 67 12754 33 227 2.4 4 ″ 0.8806 9.0 67 130 55 33 202 2.5 5 15 0.8692 7.9 47 11032 20 193 2.5 6 20 0.8625 8.8 28 93 20 12 175 2.4 B* 20 0.8623 9.4 22 9520 12 190 1.9 23° C. 23° C. Flex 2% Secant Load at Elongation 1 Cycle300% Compress. Blocking Modulus Modulus Break at Break Recovery SetStrength Ex. (MPa) (MPa) (MPa) (percent) (percent) (percent) (KPa) A*175 152 30 830 — — — 1 178 155 28 850 — — — 2 166 141 24 721 — — — 3 179155 27 802 — — — 4 189 158 27 842 — — — 5 41 30 17 1069 67 34 0 6 19 117 1,187 70 41 3 B* 29 15 5 900 56 60 6

TABLE 5 Polymer Optical Properties 45° Gloss Internal Ex. Clarity (%)(%) Haze (%) clarity gloss haze A* 75 57 23 0.5167 0.3911 1.2 1 75 63 120.3742 0.1414 0.1923 2 75 62 12 0.6148 0.3209 0.2588 3 75 63 12 0.72660.1516 0.2345 4 75 60 15 0.5495 0.3033 0.2588 5 76 61 15 0.2915 0.46150.614 6 80 63 12 0.3781 1.215 0.2168 B* 68 54 33 0.3701 0.9899 0.3781

1. A single reactor continuous process for the polymerization of one ormore addition polymerizable monomers to form a polymer comprisingmultiple regions or segments having differentiated polymer compositionsor properties, said process comprising: contacting an additionpolymerizable monomer or mixture of monomers under additionpolymerization conditions with a composition comprising a single olefinpolymerization catalyst, a cocatalyst and a chain shuttling agent; andforming at least some of the growing polymer chains under differentiatedprocess conditions such that two or more blocks or segments formedwithin at least some of the resulting polymer are chemically orphysically distinguishable wherein the differentiated process conditionis a monomer gradient maintained between at least two regions of thereactor.
 2. The process of claim 1 comprising forming a pseudo-blockpolymer comprising two or more intramolecular regions or segmentscomprising differing chemical or physical properties and possessing amolecular weight distribution, Mw/Mn, of less than 3.0.
 3. The processof claim 2 comprising forming a polymer mixture comprising: (1) anorganic or inorganic polymer, and (2) a the pseudo-block polymer.
 4. Aprocess according to claim 1 wherein the catalyst comprises a metalcomplex corresponding to the formula:

wherein: R¹¹ is selected from alkyl, cycloalkyl, heteroalkyl,cycloheteroalkyl, aryl, and inertly substituted derivatives thereofcontaining from 1 to 30 atoms not counting hydrogen or a divalentderivative thereof; T¹ is a divalent bridging group of from 1 to 41atoms other than hydrogen, and R¹² is a C₅₋₂₀ heteroaryl groupcontaining Lewis base functionality; M¹ is a group 4 metal; X¹ is ananionic, neutral or dianionic ligand group; x′ is a number from 0 to 5indicating the number of such X¹ groups; and bonds, optional bonds andelectron donative interactions are represented by lines, dotted linesand arrows respectively.
 5. A process according to claim 1 wherein thecatalyst comprises a metal complex corresponding to the formula:

wherein: M² is a metal of Groups 4-10 of the Periodic Table of theelements; T² is a nitrogen, oxygen or phosphorus containing group; X² ishalo, hydrocarbyl, or hydrocarbyloxy; t is one or two; x″ is a numberselected to provide charge balance; and T² and N are linked by abridging ligand.
 6. The process of claim 2 wherein the pseudo-blockcopolymer comprises in polymerized form at least one monomer selectedfrom the group consisting of ethylene, propylene and 4-methyl-1-pentene.7. The process of claim 4 wherein T¹ is 1 to 20 atoms other thanhydrogen.
 8. The process of claim 4 wherein T¹ is a mono- or di-C₁₋₂₀hydrocarbyl substituted methylene or silane group.
 9. The process ofclaim 4 wherein R¹² is pyridin-2-yl- or substituted pyridin-2-yl groupor a divalent derivative thereof.
 10. The process of claim 4 wherein M¹is hafnium.
 11. The process of claim 1 wherein the process is performedin a loop reactor.